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Schüning T, Zeug A, Strienke K, Franz P, Tsiavaliaris G, Hensel N, Viero G, Ponimaskin E, Claus P. The spinal muscular atrophy gene product regulates actin dynamics. FASEB J 2024; 38:e70055. [PMID: 39305126 DOI: 10.1096/fj.202300183r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 07/31/2024] [Accepted: 09/04/2024] [Indexed: 10/01/2024]
Abstract
Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by low levels of the Survival of Motoneuron (SMN) protein. SMN interacts with and regulates the actin-binding protein profilin2a, thereby influencing actin dynamics. Dysfunctional actin dynamics caused by SMN loss disrupts neurite outgrowth, axonal pathfinding, and formation of functional synapses in neurons. Whether the SMN protein directly interacts with and regulates filamentous (F-) and monomeric globular (G-) actin is still elusive. In a quantitative single cell approach, we show that SMN loss leads to dysregulated F-/G-actin fractions. Furthermore, quantitative assessment of cell morphology suggests an F-actin organizational defect. Interestingly, this is mediated by an interaction of SMN with G- and F-actin. In co-immunoprecipitation, in-vitro pulldown and co-localization assays, we elucidated that this interaction is independent of the SMN-profilin2a interaction. Therefore, we suggest two populations being relevant for functional actin dynamics in healthy neurons: SMN-profilin2a-actin and SMN-actin. Additionally, those two populations may influence each other and therefore regulate binding of SMN to actin. In SMA, we showed a dysregulated co-localization pattern of SMN-actin which could only partially rescued by SMN restoration. However, dysregulation of F-/G-actin fractions was reduced by SMN restoration. Taken together, our results suggest a novel molecular function of SMN in binding to actin independent from SMN-profilin2a interaction.
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Affiliation(s)
- Tobias Schüning
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany
- Department of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Andre Zeug
- Institute of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Katharina Strienke
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany
- Department of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Peter Franz
- Cellular Biophysics, Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Georgios Tsiavaliaris
- Cellular Biophysics, Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Niko Hensel
- Department of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Gabriella Viero
- Institute of Biophysics (IBF), CNR Unit at Trento, Trento, Italy
| | - Evgeni Ponimaskin
- Department of Anatomy and Cell Biology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Peter Claus
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
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Torri F, Mancuso M, Siciliano G, Ricci G. Beyond Motor Neurons in Spinal Muscular Atrophy: A Focus on Neuromuscular Junction. Int J Mol Sci 2024; 25:7311. [PMID: 39000416 PMCID: PMC11242411 DOI: 10.3390/ijms25137311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/29/2024] [Accepted: 07/02/2024] [Indexed: 07/16/2024] Open
Abstract
5q-Spinal muscular atrophy (5q-SMA) is one of the most common neuromuscular diseases due to homozygous mutations in the SMN1 gene. This leads to a loss of function of the SMN1 gene, which in the end determines lower motor neuron degeneration. Since the generation of the first mouse models of SMA neuropathology, a complex degenerative involvement of the neuromuscular junction and peripheral axons of motor nerves, alongside lower motor neurons, has been described. The involvement of the neuromuscular junction in determining disease symptoms offers a possible parallel therapeutic target. This narrative review aims at providing an overview of the current knowledge about the pathogenesis and significance of neuromuscular junction dysfunction in SMA, circulating biomarkers, outcome measures and available or developing therapeutic approaches.
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Affiliation(s)
- Francesca Torri
- Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Michelangelo Mancuso
- Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Gabriele Siciliano
- Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
| | - Giulia Ricci
- Department of Clinical and Experimental Medicine, University of Pisa, 56126 Pisa, Italy
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Machado R, Costa C, Fineza I, Ribeiro JA. Prevalence and Classification of Pediatric Neuromuscular Disorders in the Central Region of Portugal. J Child Neurol 2024; 39:233-240. [PMID: 39090974 DOI: 10.1177/08830738241256154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Neuromuscular disorders are a group of rare heterogenous diseases with profound impact on quality of life, for which overall pediatric prevalence has rarely been reported. The purpose of this study was to determine the point prevalence of pediatric neuromuscular disorders and its subcategories in the central region of Portugal. Retrospective case identification was carried out in children with neuromuscular disorders seen between 1998 and 2020 from multiple data sources. Demographics, clinical and molecular diagnoses were registered. On January 1, 2020, the point overall prevalence in the population <18 years of age was 41.20/100 000 (95% confidence interval 34.51-49.19) for all neuromuscular disorders. The main case proportion were genetic disorders (95.7%). We found a relatively higher occurrence of limb-girdle muscular dystrophies, congenital myopathies, and spinal muscular atrophy and a slightly lower occurrence of Duchenne muscular dystrophy, hereditary spastic paraparesis, and acquired neuropathies compared to previous studies in other countries. Molecular confirmation was available in 69.5% of pediatric neuromuscular patients in our cohort.Total prevalence is high in comparison with the data reported in the only previous study on the prevalence of pediatric neuromuscular disorders in our country. Our high definitive diagnostic rate underscores the importance of advances in investigative genetic techniques, particularly new sequencing technologies, in the diagnostic workup of neuromuscular patients.
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Affiliation(s)
- Rita Machado
- Neurology Department, Hospital Universitário de Coimbra, Unidade Local de Saúde de Coimbra, Coimbra, Portugal
| | - Carmen Costa
- Neuropediatrics, Centro de Desenvolvimento da Criança, Hospital Pediátrico de Coimbra, Unidade Local de Saúde de Coimbra, Coimbra, Portugal
| | - Isabel Fineza
- Neuropediatrics, Centro de Desenvolvimento da Criança, Hospital Pediátrico de Coimbra, Unidade Local de Saúde de Coimbra, Coimbra, Portugal
| | - Joana Afonso Ribeiro
- Neuropediatrics, Centro de Desenvolvimento da Criança, Hospital Pediátrico de Coimbra, Unidade Local de Saúde de Coimbra, Coimbra, Portugal
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Kaur J, Sharma A, Mundlia P, Sood V, Pandey A, Singh G, Barnwal RP. RNA-Small-Molecule Interaction: Challenging the "Undruggable" Tag. J Med Chem 2024. [PMID: 38498010 DOI: 10.1021/acs.jmedchem.3c01354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
RNA targeting, specifically with small molecules, is a relatively new and rapidly emerging avenue with the promise to expand the target space in the drug discovery field. From being "disregarded" as an "undruggable" messenger molecule to FDA approval of an RNA-targeting small-molecule drug Risdiplam, a radical change in perspective toward RNA has been observed in the past decade. RNAs serve important regulatory functions beyond canonical protein synthesis, and their dysregulation has been reported in many diseases. A deeper understanding of RNA biology reveals that RNA molecules can adopt a variety of structures, carrying defined binding pockets that can accommodate small-molecule drugs. Due to its functional diversity and structural complexity, RNA can be perceived as a prospective target for therapeutic intervention. This perspective highlights the proof of concept of RNA-small-molecule interactions, exemplified by targeting of various transcripts with functional modulators. The advent of RNA-oriented knowledge would help expedite drug discovery.
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Affiliation(s)
- Jaskirat Kaur
- Department of Biophysics, Panjab University, Chandigarh 160014, India
| | - Akanksha Sharma
- Department of Biophysics, Panjab University, Chandigarh 160014, India
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India
| | - Poonam Mundlia
- Department of Biophysics, Panjab University, Chandigarh 160014, India
| | - Vikas Sood
- Department of Biochemistry, Jamia Hamdard, New Delhi 110062, India
| | - Ankur Pandey
- Department of Chemistry, Panjab University, Chandigarh 160014, India
| | - Gurpal Singh
- University Institute of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India
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Armengol VD, Darras BT, Abulaban AA, Alshehri A, Barisic N, Ben-Omran T, Bernert G, Castiglioni C, Chien YH, Farrar MA, Kandawasvika G, Khadilkar S, Mah J, Marini-Bettolo C, Osredkar D, Pfeffer G, Piazzon FB, Pitarch Castellano I, Quijano-Roy S, Saito K, Shin JH, Vázquez-Costa JF, Walter MC, Wanigasinghe J, Xiong H, Griggs RC, Roy B. Life-Saving Treatments for Spinal Muscular Atrophy: Global Access and Availability. Neurol Clin Pract 2024; 14:e200224. [PMID: 38107546 PMCID: PMC10723640 DOI: 10.1212/cpj.0000000000200224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 11/04/2023] [Indexed: 12/19/2023]
Abstract
Background and Objectives Spinal muscular atrophy (SMA) is a neurodegenerative disorder manifesting with progressive muscle weakness and atrophy. SMA type 1 used to be fatal within the first 2 years of life, but is now treatable with therapies targeting splicing modification and gene replacement. Nusinersen, risdiplam, and onasemnogene abeparvovec-xioi improve survival, motor strength, endurance, and ability to thrive, allowing many patients to potentially attain a normal life; all have been recently approved by major regulatory agencies. Although these therapies have revolutionized the world of SMA, they are associated with a high economic burden, and access to these therapies is limited in some countries. The primary objective of this study was to compare the availability and implementation of treatment of SMA from different regions of the world. Methods In this qualitative study, we surveyed health care providers from 21 countries regarding their experiences caring for patients with SMA. The main outcome measures were provider survey responses on newborn screening, drug availability/access, barriers to treatment, and related questions. Results Twenty-four providers from 21 countries with decades of experience (mean 26 years) in treating patients with SMA responded to the survey. Nusinersen was the most available therapy for SMA. Our survey showed that while genetic testing is usually available, newborn screening is still unavailable in many countries. The provider-reported treatment cost also varied between countries, and economic burden was a major barrier in treating patients with SMA. Discussion Overall, this survey highlights the global inequality in managing patients with SMA. The spread of newborn screening is essential in ensuring improved access to care for patients with SMA. With the advancement of neurotherapeutics, more genetic diseases will soon be treatable, and addressing the global inequality in clinical care will require novel approaches to mitigate such inequality in the future.
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Affiliation(s)
- Victor D Armengol
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Basil T Darras
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Ahmad A Abulaban
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Ali Alshehri
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Nina Barisic
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Tawfeg Ben-Omran
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Guenther Bernert
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Claudia Castiglioni
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Yin-Hsiu Chien
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Michelle A Farrar
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Gwendoline Kandawasvika
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Satish Khadilkar
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Jean Mah
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Chiara Marini-Bettolo
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Damjan Osredkar
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Gerald Pfeffer
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Flavia B Piazzon
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Inmaculada Pitarch Castellano
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Susana Quijano-Roy
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Kayoko Saito
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Jin-Hong Shin
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Juan F Vázquez-Costa
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Maggie C Walter
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Jithangi Wanigasinghe
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Hui Xiong
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Robert C Griggs
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
| | - Bhaskar Roy
- Department of Neurology (VDA, BR), Yale University School of Medicine, New Haven, CT; Department of Neurology (BTD), Boston Children's Hospital, MA; Department of Medicine (AAA), King Saud Bin Abdulaziz University for Health Sciences; Neuromuscular Integrated Practice Unit (AA), Neuroscience Center, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia; Department of Pediatrics (NB), University of Zagreb Medical School, Croatia; Genetics and Genomic Medicine Division (TB-O), Sidra Medicine and Hamad Medical Corporation, Doha, Qatar; Department of Pediatrics (GB), Klinik Favoriten, Vienna, Austria; Department of Pediatrics (CC), Clínica Meds, Santiago, Chile; Department of Medical Genetics and Pediatrics (Y-HC), National Taiwan University Hospital, Taipei; Department of Neurology (MAF), Sydney Children's Hospital Network, New South Wales, Australia; Department of Paediatrics and Child Health (GK), College of Health Sciences, University of Zimbabwe, Harare; Department of Neurology (SK), Bombay Hospital, India; Department of Pediatrics (JM), University of Calgary Cumming School of Medicine, Alberta, Canada; John Walton Muscular Dystrophy Research Centre (CM-B), Newcastle University, Newcastle Upon Tyne, United Kingdom; Department of Child (DO), Adolescent, and Developmental Neurology, Children's Hospital, University Medical Centre Ljubljana, Slovenia; Department of Medical Genetics (GP), University of Calgary Cumming School of Medicine, Alberta, Canada; Neurometabolic Unit (FBP), University of Sao Paulo, Brazil; Department of Pediatrics (IPC), Hospital Universitari i Politècnic La Fe, Valencia, Spain; Child Neurology and ICU Department (SQ-R), Raymond Poincaré University Hospital (UVSQ), Garche, France; Institute of Medical Genetics (KS), Tokyo Women's Medical University, Japan; Department of Neurology (J-HS), Pusan National University Yangsan Hospital, South Korea; Neuromuscular Unit (JFV-C), Hospital Universitario y Politécnico la Fe, Valencia, Spain; Friedrich-Baur-Institute (MCW), Department of Neurology, Ludwig-Maximilians-University of Munich, Germany; Department of Paediatrics (JW), University of Colombo, Sri Lanka; Department of Pediatrics (HX), Peking University First Hospital, China; and Department of Neurology (RCG), University of Rochester Medical Center, NY
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6
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Custer SK, Gilson T, Astroski JW, Nanguneri SR, Iurillo AM, Androphy EJ. COPI coatomer subunit α-COP interacts with the RNA binding protein Nucleolin via a C-terminal dilysine motif. Hum Mol Genet 2023; 32:3263-3275. [PMID: 37658769 PMCID: PMC10656708 DOI: 10.1093/hmg/ddad140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/07/2023] [Accepted: 08/30/2023] [Indexed: 09/05/2023] Open
Abstract
The COPI coatomer subunit α-COP has been shown to co-precipitate mRNA in multiple settings, but it was unclear whether the interaction with mRNA was direct or mediated by interaction with an adapter protein. The COPI complex often interacts with proteins via C-terminal dilysine domains. A search for candidate RNA binding proteins with C-terminal dilysine motifs yielded Nucleolin, which terminates in a KKxKxx sequence. This protein was an especially intriguing candidate as it has been identified as an interacting partner for Survival Motor Neuron protein (SMN). Loss of SMN causes the neurodegenerative disease Spinal Muscular Atrophy. We have previously shown that SMN and α-COP interact and co-migrate in axons, and that overexpression of α-COP reduced phenotypic severity in cell culture and animal models of SMA. We show here that in an mRNA independent manner, endogenous Nucleolin co-precipitates endogenous α-COP and ε-COP but not β-COP which may reflect an interaction with the so-called B-subcomplex rather a complete COPI heptamer. The ability of Nucleolin to bind to α-COP requires the presence of the C-terminal KKxKxx domain of Nucleolin. Furthermore, we have generated a point mutant in the WD40 domain of α-COP which eliminates its ability to co-precipitate Nucleolin but does not interfere with precipitation of partners mediated by non-KKxKxx motifs such as the kainate receptor subunit 2. We propose that via interaction between the C-terminal dilysine motif of Nucleolin and the WD40 domain of α-COP, Nucleolin acts an adaptor to allow α-COP to interact with a population of mRNA.
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Affiliation(s)
- Sara K Custer
- Dermatology, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 139, Indianapolis, IN 46202, United States
| | - Timra Gilson
- Dermatology, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 139, Indianapolis, IN 46202, United States
| | - Jacob W Astroski
- Dermatology, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 139, Indianapolis, IN 46202, United States
| | - Siddarth R Nanguneri
- Dermatology, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 139, Indianapolis, IN 46202, United States
| | - Alyssa M Iurillo
- Indiana University School of Medicine, 340 West 10 St, Indianapolis, IN 46202, United States
| | - Elliot J Androphy
- Dermatology, Indiana University School of Medicine, 545 Barnhill Drive, Emerson Hall 139, Indianapolis, IN 46202, United States
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7
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Musawi S, Donnio LM, Zhao Z, Magnani C, Rassinoux P, Binda O, Huang J, Jacquier A, Coudert L, Lomonte P, Martinat C, Schaeffer L, Mottet D, Côté J, Mari PO, Giglia-Mari G. Nucleolar reorganization after cellular stress is orchestrated by SMN shuttling between nuclear compartments. Nat Commun 2023; 14:7384. [PMID: 37968267 PMCID: PMC10652021 DOI: 10.1038/s41467-023-42390-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 10/10/2023] [Indexed: 11/17/2023] Open
Abstract
Spinal muscular atrophy is an autosomal recessive neuromuscular disease caused by mutations in the multifunctional protein Survival of Motor Neuron, or SMN. Within the nucleus, SMN localizes to Cajal bodies, which are associated with nucleoli, nuclear organelles dedicated to the first steps of ribosome biogenesis. The highly organized structure of the nucleolus can be dynamically altered by genotoxic agents. RNAP1, Fibrillarin, and nucleolar DNA are exported to the periphery of the nucleolus after genotoxic stress and, once DNA repair is fully completed, the organization of the nucleolus is restored. We find that SMN is required for the restoration of the nucleolar structure after genotoxic stress. During DNA repair, SMN shuttles from the Cajal bodies to the nucleolus. This shuttling is important for nucleolar homeostasis and relies on the presence of Coilin and the activity of PRMT1.
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Affiliation(s)
- Shaqraa Musawi
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
- Department of Medical Laboratories Technology, College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Lise-Marie Donnio
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France.
| | - Zehui Zhao
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Charlène Magnani
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Phoebe Rassinoux
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Olivier Binda
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
- Faculty of Medicine, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, K1H 8M5, Ontario, Canada
| | - Jianbo Huang
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Arnaud Jacquier
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Laurent Coudert
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Patrick Lomonte
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Cécile Martinat
- INSERM/UEPS UMR 861, Paris Saclay Université, I-STEM, 91100, Corbeil-Essonnes, France
| | - Laurent Schaeffer
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Denis Mottet
- GIGA-Molecular Biology of Diseases, Gene Expression and Cancer Laboratory, B34 + 1, University of Liege, Avenue de l'Hôpital 1, B-4000, Liège, Belgium
| | - Jocelyn Côté
- Faculty of Medicine, Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, K1H 8M5, Ontario, Canada
| | - Pierre-Olivier Mari
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France
| | - Giuseppina Giglia-Mari
- Pathophysiology and Genetics of Neuron and Muscle (INMG-PGNM), CNRS UMR 5261, INSERM U1315, Université Claude Bernard Lyon 1, 68008, Lyon, France.
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8
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Yang XC, Desotell A, Lin MH, Paige AS, Malinowska A, Sun Y, Aik WS, Dadlez M, Tong L, Dominski Z. In vitro methylation of the U7 snRNP subunits Lsm11 and SmE by the PRMT5/MEP50/pICln methylosome. RNA (NEW YORK, N.Y.) 2023; 29:1673-1690. [PMID: 37562960 PMCID: PMC10578488 DOI: 10.1261/rna.079709.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/08/2023] [Indexed: 08/12/2023]
Abstract
U7 snRNP is a multisubunit endonuclease required for 3' end processing of metazoan replication-dependent histone pre-mRNAs. In contrast to the spliceosomal snRNPs, U7 snRNP lacks the Sm subunits D1 and D2 and instead contains two related proteins, Lsm10 and Lsm11. The remaining five subunits of the U7 heptameric Sm ring, SmE, F, G, B, and D3, are shared with the spliceosomal snRNPs. The pathway that assembles the unique ring of U7 snRNP is unknown. Here, we show that a heterodimer of Lsm10 and Lsm11 tightly interacts with the methylosome, a complex of the arginine methyltransferase PRMT5, MEP50, and pICln known to methylate arginines in the carboxy-terminal regions of the Sm proteins B, D1, and D3 during the spliceosomal Sm ring assembly. Both biochemical and cryo-EM structural studies demonstrate that the interaction is mediated by PRMT5, which binds and methylates two arginine residues in the amino-terminal region of Lsm11. Surprisingly, PRMT5 also methylates an amino-terminal arginine in SmE, a subunit that does not undergo this type of modification during the biogenesis of the spliceosomal snRNPs. An intriguing possibility is that the unique methylation pattern of Lsm11 and SmE plays a vital role in the assembly of the U7 snRNP.
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Affiliation(s)
- Xiao-Cui Yang
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Anthony Desotell
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Min-Han Lin
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Andrew S Paige
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Agata Malinowska
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Yadong Sun
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Wei Shen Aik
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Michał Dadlez
- Department of Biophysics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-106 Warsaw, Poland
- Institute of Genetics and Biotechnology, Warsaw University, 02-106 Warsaw, Poland
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Zbigniew Dominski
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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9
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Jha NN, Kim JK, Her YR, Monani UR. Muscle: an independent contributor to the neuromuscular spinal muscular atrophy disease phenotype. JCI Insight 2023; 8:e171878. [PMID: 37737261 PMCID: PMC10561723 DOI: 10.1172/jci.insight.171878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a pediatric-onset neuromuscular disorder caused by insufficient survival motor neuron (SMN) protein. SMN restorative therapies are now approved for the treatment of SMA; however, they are not curative, likely due to a combination of imperfect treatment timing, inadequate SMN augmentation, and failure to optimally target relevant organs. Here, we consider the implications of imperfect treatment administration, focusing specifically on outcomes for skeletal muscle. We examine the evidence that muscle plays a contributing role in driving neuromuscular dysfunction in SMA. Next, we discuss how SMN might regulate the health of myofibers and their progenitors. Finally, we speculate on therapeutic outcomes of failing to raise muscle SMN to healthful levels and present strategies to restore function to this tissue to ensure better treatment results.
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Affiliation(s)
- Narendra N. Jha
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Jeong-Ki Kim
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Yoon-Ra Her
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Umrao R. Monani
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
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10
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Cottam NC, Bamfo T, Harrington MA, Charvet CJ, Hekmatyar K, Tulin N, Sun J. Cerebellar structural, astrocytic, and neuronal abnormalities in the SMNΔ7 mouse model of spinal muscular atrophy. Brain Pathol 2023; 33:e13162. [PMID: 37218083 PMCID: PMC10467044 DOI: 10.1111/bpa.13162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 04/18/2023] [Indexed: 05/24/2023] Open
Abstract
Spinalmuscular atrophy (SMA) is a neuromuscular disease that affects as many as 1 in 6000 individuals at birth, making it the leading genetic cause of infant mortality. A growing number of studies indicate that SMA is a multi-system disease. The cerebellum has received little attention even though it plays an important role in motor function and widespread pathology has been reported in the cerebella of SMA patients. In this study, we assessed SMA pathology in the cerebellum using structural and diffusion magnetic resonance imaging, immunohistochemistry, and electrophysiology with the SMNΔ7 mouse model. We found a significant disproportionate loss in cerebellar volume, decrease in afferent cerebellar tracts, selective lobule-specific degeneration of Purkinje cells, abnormal lobule foliation and astrocyte integrity, and a decrease in spontaneous firing of cerebellar output neurons in the SMA mice compared to controls. Our data suggest that defects in cerebellar structure and function due to decreased survival motor neuron (SMN) levels impair the functional cerebellar output affecting motor control, and that cerebellar pathology should be addressed to achieve comprehensive treatment and therapy for SMA patients.
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Affiliation(s)
- Nicholas C. Cottam
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
| | - Tiffany Bamfo
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
| | | | - Christine J. Charvet
- Delaware Center for Neuroscience ResearchDelaware State UniversityDoverDelawareUSA
- Department of Anatomy, Physiology and PharmacologyAuburn UniversityAuburnAlabamaUSA
- Department of PsychologyDelaware State UniversityDoverDEUnited States
| | - Khan Hekmatyar
- Center for Biomedical and Brain ImagingUniversity of DelawareNewarkDelawareUSA
- Bioimaging Research Center for Biomedical and Brain ImagingUniversity of GeorgiaAthensGeorgiaUSA
| | - Nikita Tulin
- Department of NeuroscienceTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Jianli Sun
- Department of Biological SciencesDelaware State UniversityDoverDelawareUSA
- Delaware Center for Neuroscience ResearchDelaware State UniversityDoverDelawareUSA
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11
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Kushwaha AD, Kalra N, Varshney R, Saraswat D. Mitochondrial Ca 2+ overload due to altered proteostasis amplifies apoptosis in C2C12 myoblasts under hypoxia: Protective role of nanocurcumin formulation. IUBMB Life 2023; 75:673-687. [PMID: 37002613 DOI: 10.1002/iub.2720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/04/2023] [Indexed: 07/21/2023]
Abstract
Severe hypoxia triggers apoptosis leads to myofibers loss and is attributable to impaired intracellular calcium (iCa2+ ) homeostasis, resulting in reduced muscle activity. Hypoxia increases intracellular Ca2+ by activating the release of Ca2+ from iCa2+ stores, however, the effect of increased [iCa2+ ] on the mitochondria of muscle cells at high-altitude hypoxia is largely unexplored. This study examined mitochondrial Ca2+ overload due to altered expression of mitochondrial calcium uptake 1 (MICU1), that is, a gatekeeper of the mitochondrial Ca2+ uniporter, impaired mitochondrial membrane potential (ΔΨm). p53 stabilization and its translocation to the mitochondria were observed following disrupted mitochondrial membrane integrity in myoblasts under hypoxia. Furthermore, the downstream effects of p53 led to the upregulation of proapoptotic proteins (Bax, Caspase-3, and cytochrome C) in myoblasts under hypoxia. Nanocurcumin-pyrroloquinoline quinone formulation (NCF; Indian patent no. 302877), developed to address hypoxia-induced consequences, was found to be beneficial in maintaining mitochondrial Ca2+ homeostasis and limiting p53 translocation into mitochondria under hypoxia in muscle myoblasts. NCF treatment also modulates heat shock proteins and apoptosis-regulating protein expression in myoblasts. Conclusively, we proposed that mitochondrial Ca2+ overload due to altered MICU1 expression intensifies apoptosis and mitochondrial dysfunctionality. The study also reported that NCF could improve mitochondrial [Ca2+ ] homeostasis and antiapoptotic ability in C2C12 myoblasts under hypoxia.
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Affiliation(s)
- Asha D Kushwaha
- Defense Institute of Physiology and Allied Sciences, Defense Research and Development Organization (DRDO), Delhi, India
| | - Namita Kalra
- Institute of Nuclear Medicine and Allied Sciences, Defense Research and Development Organization (DRDO), Delhi, India
| | - Rajeev Varshney
- Defense Institute of Physiology and Allied Sciences, Defense Research and Development Organization (DRDO), Delhi, India
| | - Deepika Saraswat
- Defense Institute of Physiology and Allied Sciences, Defense Research and Development Organization (DRDO), Delhi, India
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12
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Nishio H, Niba ETE, Saito T, Okamoto K, Takeshima Y, Awano H. Spinal Muscular Atrophy: The Past, Present, and Future of Diagnosis and Treatment. Int J Mol Sci 2023; 24:11939. [PMID: 37569314 PMCID: PMC10418635 DOI: 10.3390/ijms241511939] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/17/2023] [Accepted: 07/21/2023] [Indexed: 08/13/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a lower motor neuron disease with autosomal recessive inheritance. The first cases of SMA were reported by Werdnig in 1891. Although the phenotypic variation of SMA led to controversy regarding the clinical entity of the disease, the genetic homogeneity of SMA was proved in 1990. Five years later, in 1995, the gene responsible for SMA, SMN1, was identified. Genetic testing of SMN1 has enabled precise epidemiological studies, revealing that SMA occurs in 1 of 10,000 to 20,000 live births and that more than 95% of affected patients are homozygous for SMN1 deletion. In 2016, nusinersen was the first drug approved for treatment of SMA in the United States. Two other drugs were subsequently approved: onasemnogene abeparvovec and risdiplam. Clinical trials with these drugs targeting patients with pre-symptomatic SMA (those who were diagnosed by genetic testing but showed no symptoms) revealed that such patients could achieve the milestones of independent sitting and/or walking. Following the great success of these trials, population-based newborn screening programs for SMA (more precisely, SMN1-deleted SMA) have been increasingly implemented worldwide. Early detection by newborn screening and early treatment with new drugs are expected to soon become the standards in the field of SMA.
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Affiliation(s)
- Hisahide Nishio
- Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe 651-2180, Japan
| | - Emma Tabe Eko Niba
- Laboratory of Molecular and Biochemical Research, Biomedical Research Core Facilities, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan;
| | - Toshio Saito
- Department of Neurology, National Hospital Organization Osaka Toneyama Medical Center, 5-1-1 Toneyama, Toyonaka 560-8552, Japan;
| | - Kentaro Okamoto
- Department of Pediatrics, Ehime Prefectural Imabari Hospital, 4-5-5 Ishi-cho, Imabari 794-0006, Japan;
| | - Yasuhiro Takeshima
- Department of Pediatrics, Hyogo Medical University, 1-1 Mukogawacho, Nishinomiya 663-8501, Japan;
| | - Hiroyuki Awano
- Organization for Research Initiative and Promotion, Research Initiative Center, Tottori University, 86 Nishi-cho, Yonago 683-8503, Japan;
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13
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Yang XC, Desotell A, Lin MH, Paige AS, Malinowska A, Sun Y, Aik WS, Dadlez M, Tong L, Dominski Z. In vitro methylation of the U7 snRNP subunits Lsm11 and SmE by the PRMT5/MEP50/pICln methylosome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.10.540203. [PMID: 37215023 PMCID: PMC10197641 DOI: 10.1101/2023.05.10.540203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
U7 snRNP is a multi-subunit endonuclease required for 3' end processing of metazoan replication-dependent histone pre-mRNAs. In contrast to the spliceosomal snRNPs, U7 snRNP lacks the Sm subunits D1 and D2 and instead contains two related proteins, Lsm10 and Lsm11. The remaining five subunits of the U7 heptameric Sm ring, SmE, F, G, B and D3, are shared with the spliceosomal snRNPs. The pathway that assembles the unique ring of U7 snRNP is unknown. Here, we show that a heterodimer of Lsm10 and Lsm11 tightly interacts with the methylosome, a complex of the arginine methyltransferase PRMT5, MEP50 and pICln known to methylate arginines in the C-terminal regions of the Sm proteins B, D1 and D3 during the spliceosomal Sm ring assembly. Both biochemical and Cryo-EM structural studies demonstrate that the interaction is mediated by PRMT5, which binds and methylates two arginine residues in the N-terminal region of Lsm11. Surprisingly, PRMT5 also methylates an N-terminal arginine in SmE, a subunit that does not undergo this type of modification during the biogenesis of the spliceosomal snRNPs. An intriguing possibility is that the unique methylation pattern of Lsm11 and SmE plays a vital role in the assembly of the U7 snRNP.
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14
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Mattar CNZ, Chan JKY, Choolani M. Gene modification therapies for hereditary diseases in the fetus. Prenat Diagn 2023; 43:674-686. [PMID: 36965009 PMCID: PMC10946994 DOI: 10.1002/pd.6347] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/20/2023] [Accepted: 03/02/2023] [Indexed: 03/27/2023]
Abstract
Proof-of-principle disease models have demonstrated the feasibility of an intrauterine gene modification therapy (in utero gene therapy (IUGT)) approach to hereditary diseases as diverse as coagulation disorders, haemoglobinopathies, neurogenetic disorders, congenital metabolic, and pulmonary diseases. Gene addition, which requires the delivery of an integrating or episomal transgene to the target cell nucleus to be transcribed, and gene editing, where the mutation is corrected within the gene of origin, have both been used successfully to increase normal protein production in a bid to reverse or arrest pathology in utero. While most experimental models have employed lentiviral, adenoviral, and adeno-associated viral vectors engineered to efficiently enter target cells, newer models have also demonstrated the applicability of non-viral lipid nanoparticles. Amelioration of pathology is dependent primarily on achieving sustained therapeutic transgene expression, silencing of transgene expression, production of neutralising antibodies, the dilutional effect of the recipient's growth on the mass of transduced cells, and the degree of pre-existing cellular damage. Safety assessment of any IUGT strategy will require long-term postnatal surveillance of both the fetal recipient and the maternal bystander for cell and genome toxicity, oncogenic potential, immune-responsiveness, and germline mutation. In this review, we discuss advances in the field and the push toward clinical translation of IUGT.
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Affiliation(s)
- Citra N. Z. Mattar
- Yong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
- National University Health SystemsSingaporeSingapore
| | - Jerry K. Y. Chan
- KK Women's and Children's HospitalSingaporeSingapore
- Duke‐NUS Medical SchoolSingaporeSingapore
| | - Mahesh Choolani
- Yong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
- National University Health SystemsSingaporeSingapore
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15
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Andersen J, Thom N, Shadrach JL, Chen X, Onesto MM, Amin ND, Yoon SJ, Li L, Greenleaf WJ, Müller F, Pașca AM, Kaltschmidt JA, Pașca SP. Single-cell transcriptomic landscape of the developing human spinal cord. Nat Neurosci 2023; 26:902-914. [PMID: 37095394 DOI: 10.1038/s41593-023-01311-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/20/2023] [Indexed: 04/26/2023]
Abstract
Understanding spinal cord assembly is essential to elucidate how motor behavior is controlled and how disorders arise. The human spinal cord is exquisitely organized, and this complex organization contributes to the diversity and intricacy of motor behavior and sensory processing. But how this complexity arises at the cellular level in the human spinal cord remains unknown. Here we transcriptomically profiled the midgestation human spinal cord with single-cell resolution and discovered remarkable heterogeneity across and within cell types. Glia displayed diversity related to positional identity along the dorso-ventral and rostro-caudal axes, while astrocytes with specialized transcriptional programs mapped into white and gray matter subtypes. Motor neurons clustered at this stage into groups suggestive of alpha and gamma neurons. We also integrated our data with multiple existing datasets of the developing human spinal cord spanning 22 weeks of gestation to investigate the cell diversity over time. Together with mapping of disease-related genes, this transcriptomic mapping of the developing human spinal cord opens new avenues for interrogating the cellular basis of motor control in humans and guides human stem cell-based models of disease.
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Affiliation(s)
- Jimena Andersen
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
- Department of Human Genetics, Emory University, Atlanta, GA, USA
| | - Nicholas Thom
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
| | | | - Xiaoyu Chen
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
| | - Massimo Mario Onesto
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
- Neurosciences Graduate Program, Stanford University, Stanford, CA, USA
| | - Neal D Amin
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
| | - Se-Jin Yoon
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA
| | - Li Li
- Department of Human Genetics, Emory University, Atlanta, GA, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Fabian Müller
- Department of Genetics, Stanford University, Stanford, CA, USA
- Center for Bioinformatics, Saarland University, Saarbrücken, Germany
| | - Anca M Pașca
- Department of Pediatrics, Division of Neonatology, Stanford University, Stanford, CA, USA
| | | | - Sergiu P Pașca
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA.
- Stanford Brain Organogenesis, Wu Tsai Neurosciences Institute, Stanford, CA, USA.
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16
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Arbab M, Matuszek Z, Kray KM, Du A, Newby GA, Blatnik AJ, Raguram A, Richter MF, Zhao KT, Levy JM, Shen MW, Arnold WD, Wang D, Xie J, Gao G, Burghes AHM, Liu DR. Base editing rescue of spinal muscular atrophy in cells and in mice. Science 2023; 380:eadg6518. [PMID: 36996170 PMCID: PMC10270003 DOI: 10.1126/science.adg6518] [Citation(s) in RCA: 53] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/21/2023] [Indexed: 04/01/2023]
Abstract
Spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, arises from survival motor neuron (SMN) protein insufficiency resulting from SMN1 loss. Approved therapies circumvent endogenous SMN regulation and require repeated dosing or may wane. We describe genome editing of SMN2, an insufficient copy of SMN1 harboring a C6>T mutation, to permanently restore SMN protein levels and rescue SMA phenotypes. We used nucleases or base editors to modify five SMN2 regulatory regions. Base editing converted SMN2 T6>C, restoring SMN protein levels to wild type. Adeno-associated virus serotype 9-mediated base editor delivery in Δ7SMA mice yielded 87% average T6>C conversion, improved motor function, and extended average life span, which was enhanced by one-time base editor and nusinersen coadministration (111 versus 17 days untreated). These findings demonstrate the potential of a one-time base editing treatment for SMA.
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Affiliation(s)
- Mandana Arbab
- Department of Neurology, Rosamund Stone Zander Translational Neuroscience Center, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Zaneta Matuszek
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Kaitlyn M. Kray
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA
| | - Ailing Du
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA 01605, USA
| | - Gregory A. Newby
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Anton J. Blatnik
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA
| | - Aditya Raguram
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Michelle F. Richter
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Kevin T. Zhao
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Jonathan M. Levy
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Max W. Shen
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Computational and Systems Biology Program, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - W. David Arnold
- Department of Neurology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA
- NextGen Precision Health, University of Missouri, Columbia, MO 65212, USA
| | - Dan Wang
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA 01605, USA
- Horae Gene Therapy Center and RNA Therapeutics Institute, University of Massachusetts, Medical School, Worcester, MA 01605, USA
| | - Jun Xie
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA 01605, USA
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts, Medical School, Worcester, MA 01605, USA
- Microbiology and Physiological Systems, University of Massachusetts, Medical School, Worcester, MA 01605, USA
| | - Arthur H. M. Burghes
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA
| | - David R. Liu
- Merkin Institute of Transformative Technologies in Healthcare, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA 02138, USA
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17
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Issahaku AR, Ibrahim MAA, Mukelabai N, Soliman MES. Intermolecular And Dynamic Investigation of The Mechanism of Action of Reldesemtiv on Fast Skeletal Muscle Troponin Complex Toward the Treatment of Impaired Muscle Function. Protein J 2023:10.1007/s10930-023-10091-y. [PMID: 36959428 DOI: 10.1007/s10930-023-10091-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2023] [Indexed: 03/25/2023]
Abstract
Muscle weakness as a secondary feature of attenuated neuronal input often leads to disability and sometimes death in patients with neurogenic neuromuscular diseases. These impaired muscle function has been observed in several diseases including amyotrophic lateral sclerosis, Charcot-Marie-Tooth, spinal muscular atrophy and Myasthenia gravis. This has spurred the search for small molecules which could activate fast skeletal muscle troponin complex as a means to increase muscle strength. Discovered small molecules have however been punctuated by off-target and side effects leading to the development of the second-generation small molecule, Reldesemtiv. In this study, we investigated the impact of Reldesemtiv binding to the fast skeletal troponin complex and the molecular determinants that condition the therapeutic prowess of Redesemtiv through computational techniques. It was revealed that Reldesemtiv binding possibly potentiates troponin C compacting characterized by reduced exposure to solvent molecules which could favor the slow release of calcium ions and the resultant sensitization of the subunit to calcium. These conformational changes were underscored by conventional and carbon hydrogen bonds, pi-alkyl, pi-sulfur and halogen interactions between Reldesemtiv the binding site residues. Arg113 (-3.96 kcal/mol), Met116 (-2.23 kcal/mol), Val114 (-1.28 kcal/mol) and Met121 (-0.63 kcal/mol) of the switch region of the inhibitory subunit were among the residues that contributed the most to the total free binding energy of Reldesemtiv highlighting their importance. These findings present useful insights which could lay the foundation for the development of fast skeletal muscle small molecule activators with high specificity and potency.
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Affiliation(s)
- Abdul Rashid Issahaku
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa
- West African Centre for Computational Research and Innovation, Accra, Ghana
| | - Mahmoud A A Ibrahim
- CompChem Research Group, Chemistry Department, Faculty of Science, Minia University, Minia, 61519, Egypt
| | - Namutula Mukelabai
- Department of Physiotherapy, School of Health Sciences, University of KwaZulu- Natal, Westville Campus, Durban, 4001, South Africa
| | - Mahmoud E S Soliman
- Molecular Bio-Computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa.
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18
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CNS Delivery of Nucleic Acid Therapeutics: Beyond the Blood-Brain Barrier and Towards Specific Cellular Targeting. Pharm Res 2023; 40:77-105. [PMID: 36380168 DOI: 10.1007/s11095-022-03433-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 11/03/2022] [Indexed: 11/16/2022]
Abstract
Nucleic acid-based therapeutic molecules including small interfering RNA (siRNA), microRNA(miRNA), antisense oligonucleotides (ASOs), messenger RNA (mRNA), and DNA-based gene therapy have tremendous potential for treating diseases in the central nervous system (CNS). However, achieving clinically meaningful delivery to the brain and particularly to target cells and sub-cellular compartments is typically very challenging. Mediating cell-specific delivery in the CNS would be a crucial advance that mitigates off-target effects and toxicities. In this review, we describe these challenges and provide contemporary evidence of advances in cellular and sub-cellular delivery using a variety of delivery mechanisms and alternative routes of administration, including the nose-to-brain approach. Strategies to achieve subcellular localization, endosomal escape, cytosolic bioavailability, and nuclear transfer are also discussed. Ultimately, there are still many challenges to translating these experimental strategies into effective and clinically viable approaches for treating patients.
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19
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Glascock J, Darras BT, Crawford TO, Sumner CJ, Kolb SJ, DiDonato C, Elsheikh B, Howell K, Farwell W, Valente M, Petrillo M, Tingey J, Jarecki J. Identifying Biomarkers of Spinal Muscular Atrophy for Further Development. J Neuromuscul Dis 2023; 10:937-954. [PMID: 37458045 PMCID: PMC10578234 DOI: 10.3233/jnd-230054] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by bi-allelic, recessive mutations of the survival motor neuron 1 (SMN1) gene and reduced expression levels of the survival motor neuron (SMN) protein. Degeneration of alpha motor neurons in the spinal cord causes progressive skeletal muscle weakness. The wide range of disease severities, variable rates of decline, and heterogenous clinical responses to approved disease-modifying treatment remain poorly understood and limit the ability to optimize treatment for patients. Validation of a reliable biomarker(s) with the potential to support early diagnosis, inform disease prognosis and therapeutic suitability, and/or confirm response to treatment(s) represents a significant unmet need in SMA. OBJECTIVES The SMA Multidisciplinary Biomarkers Working Group, comprising 11 experts in a variety of relevant fields, sought to determine the most promising candidate biomarker currently available, determine key knowledge gaps, and recommend next steps toward validating that biomarker for SMA. METHODS The Working Group engaged in a modified Delphi process to answer questions about candidate SMA biomarkers. Members participated in six rounds of reiterative surveys that were designed to build upon previous discussions. RESULTS The Working Group reached a consensus that neurofilament (NF) is the candidate biomarker best poised for further development. Several important knowledge gaps were identified, and the next steps toward filling these gaps were proposed. CONCLUSIONS NF is a promising SMA biomarker with the potential for prognostic, predictive, and pharmacodynamic capabilities. The Working Group has identified needed information to continue efforts toward the validation of NF as a biomarker for SMA.
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Affiliation(s)
| | - Basil T. Darras
- Boston Children’s Hospital/Harvard Medical School, Boston, MA, USA
| | - Thomas O. Crawford
- Johns Hopkins University School of Medicine Departments of Neurology and Neuroscience, Department of Neurology and Pediatrics, Baltimore, MD, USA
| | - Charlotte J. Sumner
- Johns Hopkins University School of Medicine Departments of Neurology and Neuroscience, Department of Neurology and Pediatrics, Baltimore, MD, USA
| | - Stephen J. Kolb
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
- Department of Biological Chemistry & Pharmacology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | | | - Bakri Elsheikh
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Kelly Howell
- Spinal Muscular Atrophy Foundation, Jackson, WY, USA
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20
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Day JW, Howell K, Place A, Long K, Rossello J, Kertesz N, Nomikos G. Advances and limitations for the treatment of spinal muscular atrophy. BMC Pediatr 2022; 22:632. [PMID: 36329412 PMCID: PMC9632131 DOI: 10.1186/s12887-022-03671-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 10/16/2022] [Indexed: 11/06/2022] Open
Abstract
Spinal muscular atrophy (5q-SMA; SMA), a genetic neuromuscular condition affecting spinal motor neurons, is caused by defects in both copies of the SMN1 gene that produces survival motor neuron (SMN) protein. The highly homologous SMN2 gene primarily expresses a rapidly degraded isoform of SMN protein that causes anterior horn cell degeneration, progressive motor neuron loss, skeletal muscle atrophy and weakness. Severe cases result in limited mobility and ventilatory insufficiency. Untreated SMA is the leading genetic cause of death in young children. Recently, three therapeutics that increase SMN protein levels in patients with SMA have provided incremental improvements in motor function and developmental milestones and prevented the worsening of SMA symptoms. While the therapeutic approaches with Spinraza®, Zolgensma®, and Evrysdi® have a clinically significant impact, they are not curative. For many patients, there remains a significant disease burden. A potential combination therapy under development for SMA targets myostatin, a negative regulator of muscle mass and strength. Myostatin inhibition in animal models increases muscle mass and function. Apitegromab is an investigational, fully human, monoclonal antibody that specifically binds to proforms of myostatin, promyostatin and latent myostatin, thereby inhibiting myostatin activation. A recently completed phase 2 trial demonstrated the potential clinical benefit of apitegromab by improving or stabilizing motor function in patients with Type 2 and Type 3 SMA and providing positive proof-of-concept for myostatin inhibition as a target for managing SMA. The primary goal of this manuscript is to orient physicians to the evolving landscape of SMA treatment.
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Affiliation(s)
- John W Day
- Department of Neurology, Stanford University, Stanford, CA, USA
| | - Kelly Howell
- Spinal Muscular Atrophy Foundation, New York, NY, USA
| | | | | | - Jose Rossello
- Scholar Rock, Inc, 301 Binney St, Cambridge, MA, USA
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21
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Woschitz V, Mei I, Hedlund E, Murray LM. Mouse models of SMA show divergent patterns of neuronal vulnerability and resilience. Skelet Muscle 2022; 12:22. [PMID: 36089582 PMCID: PMC9465884 DOI: 10.1186/s13395-022-00305-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 08/24/2022] [Indexed: 11/21/2022] Open
Abstract
Background Spinal muscular atrophy (SMA) is a form of motor neuron disease affecting primarily children characterised by the loss of lower motor neurons (MNs). Breakdown of the neuromuscular junctions (NMJs) is an early pathological event in SMA. However, not all motor neurons are equally vulnerable, with some populations being lost early in the disease while others remain intact at the disease end-stage. A thorough understanding of the basis of this selective vulnerability will give critical insight into the factors which prohibit pathology in certain motor neuron populations and consequently help identify novel neuroprotective strategies. Methods To retrieve a comprehensive understanding of motor neuron susceptibility in SMA, we mapped NMJ pathology in 20 muscles from the Smn2B/- SMA mouse model and cross-compared these data with published data from three other commonly used mouse models. To gain insight into the molecular mechanisms regulating selective resilience and vulnerability, we analysed published RNA sequencing data acquired from differentially vulnerable motor neurons from two different SMA mouse models. Results In the Smn2B/- mouse model of SMA, we identified substantial NMJ loss in the muscles from the core, neck, proximal hind limbs and proximal forelimbs, with a marked reduction in denervation in the distal limbs and head. Motor neuron cell body loss was greater at T5 and T11 compared with L5. We subsequently show that although widespread denervation is observed in each SMA mouse model (with the notable exception of the Taiwanese model), all models have a distinct pattern of selective vulnerability. A comparison of previously published data sets reveals novel transcripts upregulated with a disease in selectively resistant motor neurons, including genes involved in axonal transport, RNA processing and mitochondrial bioenergetics. Conclusions Our work demonstrates that the Smn2B/- mouse model shows a pattern of selective vulnerability which bears resemblance to the regional pathology observed in SMA patients. We found drastic differences in patterns of selective vulnerability across the four SMA mouse models, which is critical to consider during experimental design. We also identified transcript groups that potentially contribute to the protection of certain motor neurons in SMA mouse models. Supplementary Information The online version contains supplementary material available at 10.1186/s13395-022-00305-9.
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22
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Detering NT, Schüning T, Hensel N, Claus P. The phospho-landscape of the survival of motoneuron protein (SMN) protein: relevance for spinal muscular atrophy (SMA). Cell Mol Life Sci 2022; 79:497. [PMID: 36006469 PMCID: PMC11071818 DOI: 10.1007/s00018-022-04522-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 07/27/2022] [Accepted: 08/09/2022] [Indexed: 11/03/2022]
Abstract
Spinal muscular atrophy (SMA) is caused by low levels of the survival of motoneuron (SMN) Protein leading to preferential degeneration of lower motoneurons in the ventral horn of the spinal cord and brain stem. However, the SMN protein is ubiquitously expressed and there is growing evidence of a multisystem phenotype in SMA. Since a loss of SMN function is critical, it is important to decipher the regulatory mechanisms of SMN function starting on the level of the SMN protein itself. Posttranslational modifications (PTMs) of proteins regulate multiple functions and processes, including activity, cellular trafficking, and stability. Several PTM sites have been identified within the SMN sequence. Here, we map the identified SMN PTMs highlighting phosphorylation as a key regulator affecting localization, stability and functions of SMN. Furthermore, we propose SMN phosphorylation as a crucial factor for intracellular interaction and cellular distribution of SMN. We outline the relevance of phosphorylation of the spinal muscular atrophy (SMA) gene product SMN with regard to basic housekeeping functions of SMN impaired in this neurodegenerative disease. Finally, we compare SMA patient mutations with putative and verified phosphorylation sites. Thus, we emphasize the importance of phosphorylation as a cellular modulator in a clinical perspective as a potential additional target for combinatorial SMA treatment strategies.
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Affiliation(s)
- Nora Tula Detering
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Tobias Schüning
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Niko Hensel
- Ottawa Hospital Research Institute (OHRI), Ottawa, Canada
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Peter Claus
- SMATHERIA gGmbH - Non-Profit Biomedical Research Institute, Hannover, Germany.
- Center for Systems Neuroscience (ZSN), Hannover, Germany.
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23
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Khayrullina G, Alipio‐Gloria ZA, Deguise M, Gagnon S, Chehade L, Stinson M, Belous N, Bergman EM, Lischka FW, Rotty J, Dalgard CL, Kothary R, Johnson KA, Burnett BG. Survival motor neuron protein deficiency alters microglia reactivity. Glia 2022; 70:1337-1358. [PMID: 35373853 PMCID: PMC9081169 DOI: 10.1002/glia.24177] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 03/20/2022] [Accepted: 03/25/2022] [Indexed: 12/31/2022]
Abstract
Survival motor neuron (SMN) protein deficiency results in loss of alpha motor neurons and subsequent muscle atrophy in patients with spinal muscular atrophy (SMA). Reactive microglia have been reported in SMA mice and depleting microglia rescues the number of proprioceptive synapses, suggesting a role in SMA pathology. Here, we explore the contribution of lymphocytes on microglia reactivity in SMA mice and investigate how SMN deficiency alters the reactive profile of human induced pluripotent stem cell (iPSC)-derived microglia. We show that microglia adopt a reactive morphology in spinal cords of SMA mice. Ablating lymphocytes did not alter the reactive morphology of SMA microglia and did not improve the survival or motor function of SMA mice, indicating limited impact of peripheral immune cells on the SMA phenotype. We found iPSC-derived SMA microglia adopted an amoeboid morphology and displayed a reactive transcriptome profile, increased cell migration, and enhanced phagocytic activity. Importantly, cell morphology and electrophysiological properties of motor neurons were altered when they were incubated with conditioned media from SMA microglia. Together, these data reveal that SMN-deficient microglia adopt a reactive profile and exhibit an exaggerated inflammatory response with potential impact on SMA neuropathology.
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Affiliation(s)
- Guzal Khayrullina
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | | | - Marc‐Olivier Deguise
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanada
- Department of PediatricsChildren's Hospital of Eastern OntarioOttawaOntarioCanada
| | - Sabrina Gagnon
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
| | - Lucia Chehade
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanada
| | - Matthew Stinson
- Department of BiochemistryUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | - Natalya Belous
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | - Elizabeth M. Bergman
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | - Fritz W. Lischka
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | - Jeremy Rotty
- Department of BiochemistryUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
| | - Clifton L. Dalgard
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
- The American Genome CenterUniformed Services University of the Health SciencesBethesdaMarylandUSA
| | - Rashmi Kothary
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanada
- Department of MedicineUniversity of OttawaOttawaOntarioCanada
| | | | - Barrington G. Burnett
- Department of Anatomy, Physiology, and GeneticsUniformed Services University of the Health Sciences, F. Edward Hebert School of MedicineBethesdaMarylandUSA
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24
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Cuartas J, Gangwani L. R-loop Mediated DNA Damage and Impaired DNA Repair in Spinal Muscular Atrophy. Front Cell Neurosci 2022; 16:826608. [PMID: 35783101 PMCID: PMC9243258 DOI: 10.3389/fncel.2022.826608] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 05/23/2022] [Indexed: 12/02/2022] Open
Abstract
Defects in DNA repair pathways are a major cause of DNA damage accumulation leading to genomic instability and neurodegeneration. Efficient DNA damage repair is critical to maintain genomicstability and support cell function and viability. DNA damage results in the activation of cell death pathways, causing neuronal death in an expanding spectrum of neurological disorders, such as amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD), Alzheimer’s disease (AD), and spinal muscular atrophy (SMA). SMA is a neurodegenerative disorder caused by mutations in the Survival Motor Neuron 1 (SMN1) gene. SMA is characterized by the degeneration of spinal cord motor neurons due to low levels of the SMN protein. The molecular mechanism of selective motor neuron degeneration in SMA was unclear for about 20 years. However, several studies have identified biochemical and molecular mechanisms that may contribute to the predominant degeneration of motor neurons in SMA, including the RhoA/ROCK, the c-Jun NH2-terminal kinase (JNK), and p53-mediated pathways, which are involved in mediating DNA damage-dependent cell death. Recent studies provided insight into selective degeneration of motor neurons, which might be caused by accumulation of R-loop-mediated DNA damage and impaired non-homologous end joining (NHEJ) DNA repair pathway leading to genomic instability. Here, we review the latest findings involving R-loop-mediated DNA damage and defects in neuron-specific DNA repair mechanisms in SMA and discuss these findings in the context of other neurodegenerative disorders linked to DNA damage.
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Affiliation(s)
- Juliana Cuartas
- Center of Emphasis in Neurosciences, Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX, United States
| | - Laxman Gangwani
- Center of Emphasis in Neurosciences, Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center El Paso, El Paso, TX, United States
- Francis Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center El Paso, El Paso, TX, United States
- *Correspondence: Laxman Gangwani
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25
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Kubinski S, Claus P. Protein Network Analysis Reveals a Functional Connectivity of Dysregulated Processes in ALS and SMA. Neurosci Insights 2022; 17:26331055221087740. [PMID: 35372839 PMCID: PMC8966079 DOI: 10.1177/26331055221087740] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 02/28/2022] [Indexed: 01/09/2023] Open
Abstract
Spinal Muscular Atrophy (SMA) and Amyotrophic Lateral Sclerosis (ALS) are neurodegenerative diseases which are characterized by the loss of motoneurons within the central nervous system. SMA is a monogenic disease caused by reduced levels of the Survival of motoneuron protein, whereas ALS is a multi-genic disease with over 50 identified disease-causing genes and involvement of environmental risk factors. Although these diseases have different causes, they partially share identical phenotypes and pathomechanisms. To analyze and identify functional connections and to get a global overview of altered pathways in both diseases, protein network analyses are commonly used. Here, we used an in silico tool to test for functional associations between proteins that are involved in actin cytoskeleton dynamics, fatty acid metabolism, skeletal muscle metabolism, stress granule dynamics as well as SMA or ALS risk factors, respectively. In network biology, interactions are represented by edges which connect proteins (nodes). Our approach showed that only a few edges are necessary to present a complex protein network of different biological processes. Moreover, Superoxide dismutase 1, which is mutated in ALS, and the actin-binding protein profilin1 play a central role in the connectivity of the aforementioned pathways. Our network indicates functional links between altered processes that are described in either ALS or SMA. These links may not have been considered in the past but represent putative targets to restore altered processes and reveal overlapping pathomechanisms in both diseases.
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Affiliation(s)
- Sabrina Kubinski
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Peter Claus
- Center for Systems Neuroscience (ZSN), Hannover, Germany
- SMATHERIA gGmbH – Non-Profit Biomedical Research Institute, Hannover, Germany
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26
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Jacquier V, Prévot M, Gostan T, Bordonné R, Benkhelifa-Ziyyat S, Barkats M, Soret J. Splicing efficiency of minor introns in a mouse model of SMA predominantly depends on their branchpoint sequence and can involve the contribution of major spliceosome components. RNA (NEW YORK, N.Y.) 2022; 28:303-319. [PMID: 34893560 PMCID: PMC8848931 DOI: 10.1261/rna.078329.120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/22/2021] [Indexed: 06/14/2023]
Abstract
Spinal muscular atrophy (SMA) is a devastating neurodegenerative disease caused by reduced amounts of the ubiquitously expressed Survival of Motor Neuron (SMN) protein. In agreement with its crucial role in the biogenesis of spliceosomal snRNPs, SMN-deficiency is correlated to numerous splicing alterations in patient cells and various tissues of SMA mouse models. Among the snRNPs whose assembly is impacted by SMN-deficiency, those involved in the minor spliceosome are particularly affected. Importantly, splicing of several, but not all U12-dependent introns has been shown to be affected in different SMA models. Here, we have investigated the molecular determinants of this differential splicing in spinal cords from SMA mice. We show that the branchpoint sequence (BPS) is a key element controlling splicing efficiency of minor introns. Unexpectedly, splicing of several minor introns with suboptimal BPS is not affected in SMA mice. Using in vitro splicing experiments and oligonucleotides targeting minor or major snRNAs, we show for the first time that splicing of these introns involves both the minor and major machineries. Our results strongly suggest that splicing of a subset of minor introns is not affected in SMA mice because components of the major spliceosome compensate for the loss of minor splicing activity.
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Affiliation(s)
- Valentin Jacquier
- Institut de Génétique Moléculaire de Montpellier, Univ Montpellier, CNRS, Montpellier 34293, France
| | - Manon Prévot
- Institut de Génétique Moléculaire de Montpellier, Univ Montpellier, CNRS, Montpellier 34293, France
| | - Thierry Gostan
- Institut de Génétique Moléculaire de Montpellier, Univ Montpellier, CNRS, Montpellier 34293, France
| | - Rémy Bordonné
- Institut de Génétique Moléculaire de Montpellier, Univ Montpellier, CNRS, Montpellier 34293, France
| | - Sofia Benkhelifa-Ziyyat
- Centre de Recherche en Myologie (CRM), Institut de Myologie, Sorbonne Universités, UPMC Univ Paris 06, Inserm UMRS974, GH Pitié Salpêtrière, Paris 75013, France
| | - Martine Barkats
- Centre de Recherche en Myologie (CRM), Institut de Myologie, Sorbonne Universités, UPMC Univ Paris 06, Inserm UMRS974, GH Pitié Salpêtrière, Paris 75013, France
| | - Johann Soret
- Institut de Génétique Moléculaire de Montpellier, Univ Montpellier, CNRS, Montpellier 34293, France
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27
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Li W, Jiang C, Zhang E. Advances in the phase separation-organized membraneless organelles in cells: a narrative review. Transl Cancer Res 2022; 10:4929-4946. [PMID: 35116344 PMCID: PMC8797891 DOI: 10.21037/tcr-21-1111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 10/29/2021] [Indexed: 11/26/2022]
Abstract
Membraneless organelles (MLOs) are micro-compartments that lack delimiting membranes, concentrating several macro-molecules with a high local concentration in eukaryotic cells. Recent studies have shown that MLOs have pivotal roles in multiple biological processes, including gene transcription, RNA metabolism, translation, protein modification, and signal transduction. These biological processes in cells have essential functions in many diseases, such as cancer, neurodegenerative diseases, and virus-related diseases. The liquid-liquid phase separation (LLPS) microenvironment within cells is thought to be the driving force for initiating the formation of micro-compartments with a liquid-like property, becoming an important organizing principle for MLOs to mediate organism responses. In this review, we comprehensively elucidated the formation of these MLOs and the relationship between biological functions and associated diseases. The mechanisms underlying the influence of protein concentration and valency on phase separation in cells are also discussed. MLOs undergoing the LLPS process have diverse functions, including stimulation of some adaptive and reversible responses to alter the transcriptional or translational processes, regulation of the concentrations of biomolecules in living cells, and maintenance of cell morphogenesis. Finally, we highlight that the development of this field could pave the way for developing novel therapeutic strategies for the treatment of LLPS-related diseases based on the understanding of phase separation in the coming years.
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Affiliation(s)
- Weihan Li
- Department of Immunology, School of Medicine, Nantong University, Nantong, China
| | - Chenwei Jiang
- Department of Immunology, School of Medicine, Nantong University, Nantong, China
| | - Erhao Zhang
- Department of Immunology, School of Medicine, Nantong University, Nantong, China.,Laboratory of Medical Science, School of Medicine, Nantong University, Nantong, China
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28
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Chilcott EM, Muiruri EW, Hirst TC, Yáñez-Muñoz RJ. Systematic review and meta-analysis determining the benefits of in vivo genetic therapy in spinal muscular atrophy rodent models. Gene Ther 2022; 29:498-512. [PMID: 34611322 PMCID: PMC9482879 DOI: 10.1038/s41434-021-00292-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/30/2021] [Accepted: 09/12/2021] [Indexed: 01/31/2023]
Abstract
Spinal muscular atrophy (SMA) is a severe childhood neuromuscular disease for which two genetic therapies, Nusinersen (Spinraza, an antisense oligonucleotide), and AVXS-101 (Zolgensma, an adeno-associated viral vector of serotype 9 AAV9), have recently been approved. We investigated the pre-clinical development of SMA genetic therapies in rodent models and whether this can predict clinical efficacy. We have performed a systematic review of relevant publications and extracted median survival and details of experimental design. A random effects meta-analysis was used to estimate and compare efficacy. We stratified by experimental design (type of genetic therapy, mouse model, route and time of administration) and sought any evidence of publication bias. 51 publications were identified containing 155 individual comparisons, comprising 2573 animals in total. Genetic therapies prolonged survival in SMA mouse models by 3.23-fold (95% CI 2.75-3.79) compared to controls. Study design characteristics accounted for significant heterogeneity between studies and greatly affected observed median survival ratios. Some evidence of publication bias was found. These data are consistent with the extended average lifespan of Spinraza- and Zolgensma-treated children in the clinic. Together, these results support that SMA has been particularly amenable to genetic therapy approaches and highlight SMA as a trailblazer for therapeutic development.
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Affiliation(s)
- Ellie M. Chilcott
- grid.4970.a0000 0001 2188 881XAGCTlab.org, Centre of Gene and Cell Therapy, Centre for Biomedical Sciences, Department of Biological Sciences, School of Life Sciences and Environment, Royal Holloway University of London, TW20 0EX London, UK ,Present Address: Institute for Women’s Health, UCL, 86-96 Chenies Mews, London, WC1E 6HX UK
| | - Evalyne W. Muiruri
- grid.4970.a0000 0001 2188 881XAGCTlab.org, Centre of Gene and Cell Therapy, Centre for Biomedical Sciences, Department of Biological Sciences, School of Life Sciences and Environment, Royal Holloway University of London, TW20 0EX London, UK
| | - Theodore C. Hirst
- grid.416232.00000 0004 0399 1866Department of Neurosurgery, Royal Victoria Hospital, Belfast, BT12 6BA UK
| | - Rafael J. Yáñez-Muñoz
- grid.4970.a0000 0001 2188 881XAGCTlab.org, Centre of Gene and Cell Therapy, Centre for Biomedical Sciences, Department of Biological Sciences, School of Life Sciences and Environment, Royal Holloway University of London, TW20 0EX London, UK
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29
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Varderidou-Minasian S, Verheijen BM, Harschnitz O, Kling S, Karst H, van der Pol WL, Pasterkamp RJ, Altelaar M. Spinal Muscular Atrophy Patient iPSC-Derived Motor Neurons Display Altered Proteomes at Early Stages of Differentiation. ACS OMEGA 2021; 6:35375-35388. [PMID: 34984269 PMCID: PMC8717385 DOI: 10.1021/acsomega.1c04688] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/24/2021] [Indexed: 05/08/2023]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder characterized by loss of motor neurons (MN) in the spinal cord leading to progressive muscle atrophy and weakness. SMA is caused by mutations in the survival motor neuron 1 (SMN1) gene, resulting in reduced levels of survival motor neuron (SMN) protein. The mechanisms that link SMN deficiency to selective motor neuron dysfunction in SMA remain largely unknown. We present here, for the first time, a comprehensive quantitative TMT-10plex proteomics analysis that covers the development of induced pluripotent stem cell-derived MNs from both healthy individuals and SMA patients. We show that the proteomes of SMA samples segregate from controls already at early stages of neuronal differentiation. The altered proteomic signature in SMA MNs is associated with mRNA splicing, ribonucleoprotein biogenesis, organelle organization, cellular biogenesis, and metabolic processes. We highlight several known SMN-binding partners and evaluate their expression changes during MN differentiation. In addition, we compared our study to human and mouse in vivo proteomic studies revealing distinct and similar signatures. Altogether, our work provides a comprehensive resource of molecular events during early stages of MN differentiation, containing potentially therapeutically interesting protein expression profiles for SMA.
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Affiliation(s)
- Suzy Varderidou-Minasian
- Biomolecular
Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular
Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584
CH Utrecht, The Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Bert M. Verheijen
- Department
of Translational Neuroscience, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CG Utrecht, The Netherlands
- Department
of Neurology and Neurosurgery, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Oliver Harschnitz
- Department
of Translational Neuroscience, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CG Utrecht, The Netherlands
- Department
of Neurology and Neurosurgery, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Sandra Kling
- Department
of Translational Neuroscience, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CG Utrecht, The Netherlands
- Department
of Neurology and Neurosurgery, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Henk Karst
- Department
of Translational Neuroscience, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - W. Ludo van der Pol
- Department
of Neurology and Neurosurgery, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - R. Jeroen Pasterkamp
- Department
of Translational Neuroscience, UMC Utrecht Brain Center, University
Medical Center Utrecht, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Maarten Altelaar
- Biomolecular
Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular
Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, 3584
CH Utrecht, The Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
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30
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McCormack NM, Villalón E, Viollet C, Soltis AR, Dalgard CL, Lorson CL, Burnett BG. Survival motor neuron deficiency slows myoblast fusion through reduced myomaker and myomixer expression. J Cachexia Sarcopenia Muscle 2021; 12:1098-1116. [PMID: 34115448 PMCID: PMC8350220 DOI: 10.1002/jcsm.12740] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 05/05/2021] [Accepted: 05/21/2021] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Spinal muscular atrophy is an inherited neurodegenerative disease caused by insufficient levels of the survival motor neuron (SMN) protein. Recently approved treatments aimed at increasing SMN protein levels have dramatically improved patient survival and have altered the disease landscape. While restoring SMN levels slows motor neuron loss, many patients continue to have smaller muscles and do not achieve normal motor milestones. While timing of treatment is important, it remains unclear why SMN restoration is insufficient to fully restore muscle size and function. We and others have shown that SMN-deficient muscle precursor cells fail to efficiently fuse into myotubes. However, the role of SMN in myoblast fusion is not known. METHODS In this study, we show that SMN-deficient myoblasts readily fuse with wild-type myoblasts, demonstrating fusion competency. Conditioned media from wild type differentiating myoblasts do not rescue the fusion deficit of SMN-deficient cells, suggesting that compromised fusion may primarily be a result of altered membrane dynamics at the cell surface. Transcriptome profiling of skeletal muscle from SMN-deficient mice revealed altered expression of cell surface fusion molecules. Finally, using cell and mouse models, we investigate if myoblast fusion can be rescued in SMN-deficient myoblast and improve the muscle pathology in SMA mice. RESULTS We found reduced expression of the muscle fusion proteins myomaker (P = 0.0060) and myomixer (P = 0.0051) in the muscle of SMA mice. Suppressing SMN expression in C2C12 myoblast cells reduces expression of myomaker (35% reduction; P < 0.0001) and myomixer, also known as myomerger and minion, (30% reduction; P < 0.0001) and restoring SMN levels only partially restores myomaker and myomixer expression. Ectopic expression of myomixer improves myofibre number (55% increase; P = 0.0006) and motor function (35% decrease in righting time; P = 0.0089) in SMA model mice and enhances motor function (82% decrease in righting time; P < 0.0001) and extends survival (28% increase; P < 0.01) when administered in combination with an antisense oligonucleotide that increases SMN protein levels. CONCLUSIONS Here, we identified reduced expression of muscle fusion proteins as a key factor in the fusion deficits of SMN-deficient myoblasts. This discovery provides a novel target to improve SMA muscle pathology and motor function, which in combination with SMN increasing therapy could enhance clinical outcomes for SMA patients.
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Affiliation(s)
- Nikki M McCormack
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MD, USA
| | - Eric Villalón
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Coralie Viollet
- Collaborative Health Initiative Research Program, Uniformed Services University of the Heath Sciences, Bethesda, MD, USA
| | - Anthony R Soltis
- Collaborative Health Initiative Research Program, Uniformed Services University of the Heath Sciences, Bethesda, MD, USA.,Henry M. Jackson Foundation, Bethesda, MD, USA
| | - Clifton L Dalgard
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MD, USA.,Collaborative Health Initiative Research Program, Uniformed Services University of the Heath Sciences, Bethesda, MD, USA.,The American Genome Center, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Christian L Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA.,Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Barrington G Burnett
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, F. Edward Hébert School of Medicine, Bethesda, MD, USA
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31
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Welsh BT, Cote SM, Meshulam D, Jackson J, Pal A, Lansita J, Kalra A. Preclinical Safety Assessment and Toxicokinetics of Apitegromab, an Antibody Targeting Proforms of Myostatin for the Treatment of Muscle-Atrophying Disease. Int J Toxicol 2021; 40:322-336. [PMID: 34255983 PMCID: PMC8326894 DOI: 10.1177/10915818211025477] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Myostatin is a negative regulator of skeletal muscle and has become a therapeutic target for muscle atrophying disorders. Although previous inhibitors of myostatin offered promising preclinical data, these therapies demonstrated a lack of specificity toward myostatin signaling and have shown limited success in the clinic. Apitegromab is a fully human, monoclonal antibody that binds to human promyostatin and latent myostatin with a high degree of specificity, without binding mature myostatin and other closely related growth factors. To support the clinical development of apitegromab, we present data from a comprehensive preclinical assessment of its pharmacology, pharmacokinetics, and safety across multiple species. In vitro studies confirmed the ability of apitegromab to inhibit the activation of promyostatin. Toxicology studies in monkeys for 4 weeks and in adult rats for up to 26 weeks showed that weekly intravenous administration of apitegromab achieved sustained serum exposure and target engagement and was well-tolerated, with no treatment-related adverse findings at the highest doses tested of up to 100 mg/kg and 300 mg/kg in monkeys and rats, respectively. Additionally, results from an 8-week juvenile rat study showed no adverse effects on any endpoint, including neurodevelopmental, motor, and reproductive outcomes at 300 mg/kg administered weekly IV. In summary, the nonclinical pharmacology, pharmacokinetic, and toxicology data demonstrate that apitegromab is a selective inhibitor of proforms of myostatin that does not exhibit toxicities observed with other myostatin pathway inhibitors. These data support the conduct of ongoing clinical studies of apitegromab in adult and pediatric patients with spinal muscular atrophy (SMA).
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Affiliation(s)
| | | | | | | | - Ajai Pal
- Scholar Rock, Inc, Cambridge, MA, USA
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32
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Downing K, Prisby R, Varanasi V, Zhou J, Pan Z, Brotto M. Old and new biomarkers for volumetric muscle loss. Curr Opin Pharmacol 2021; 59:61-69. [PMID: 34146835 DOI: 10.1016/j.coph.2021.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 12/21/2022]
Abstract
Volumetric muscle loss (VML) impacts skeletal muscles and causes damage to associated tissues such as blood vessels and other structural tissues. Despite progress in the VML field, current preclinical approaches are often ineffective at restoring muscle volume. Additional research is paramount to develop strategies that improve muscle mass and function, while restoring supporting tissues. We highlight mechanisms that govern normal muscle function that are also key players for VML, including intracellular calcium signaling/homeostasis, mitochondria signaling (calcium, reactiove oxidative species (ROS)/oxidative stress), and angiogenesis. We propose an integration of these processes within the context of emerging biomaterials that provide structural support for muscle regeneration. We posit that new biomarkers (i.e. myokines and lipid signaling mediators) may serve as sentinels of early muscle injury and regeneration. We conclude that as new ideas, approaches, and models come together, new treatments will emerge to allow the full rebuilding of skeletal muscles and functional recovery of skeletal muscles after VML.
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Affiliation(s)
- Kerrie Downing
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA
| | - Rhonda Prisby
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA
| | - Venu Varanasi
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA
| | - Jingsong Zhou
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA
| | - Zui Pan
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA.
| | - Marco Brotto
- Bone-Muscle Collaborative Sciences, College of Nursing & Health Innovation, The University of Texas at Arlington, Arlington, TX 76010, USA.
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33
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Zonisamide upregulates neuregulin-1 expression and enhances acetylcholine receptor clustering at the in vitro neuromuscular junction. Neuropharmacology 2021; 195:108637. [PMID: 34097946 DOI: 10.1016/j.neuropharm.2021.108637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 05/26/2021] [Accepted: 05/28/2021] [Indexed: 01/27/2023]
Abstract
Decreased acetylcholine receptor (AChR) clustering compromises signal transmission at the neuromuscular junction (NMJ) in myasthenia gravis, congenital myasthenic syndromes, and motor neuron diseases. Although the enhancement of AChR clustering at the NMJ is a promising therapeutic strategy for these maladies, no drug is currently available for this enhancement. We previously reported that zonisamide (ZNS), an anti-epileptic and anti-Parkinson's disease drug, enhances neurite elongation of the primary spinal motor neurons (SMNs). As nerve sprouting occurs to compensate for the loss of AChR clusters in human diseases, we examined the effects of ZNS on AChR clustering at the NMJ. To this end, we established a simple and quick co-culture system to reproducibly make in vitro NMJs using C2C12 myotubes and NSC34 motor neurons. ZNS at 1-20 μM enhanced the formation of AChR clusters dose-dependently in co-cultured C2C12 myotubes but not in agrin-treated single cultured C2C12 myotubes. We observed that molecules that conferred responsiveness to ZNS were not secreted into the co-culture medium. We found that 10 μM ZNS upregulated the expression of neuregulin-1 (Nrg1) in co-cultured cells but not in single cultured C2C12 myotubes or single cultured NSC34 motor neurons. In accordance with this observation, inhibition of the Nrg1/ErbB signaling pathways nullified the effect of 10 μM ZNS on the enhancement of AChR clustering in in vitro NMJs. Although agrin was not induced by 10 μM ZNS in co-cultured cells, anti-agrin antibody attenuated ZNS-mediated enhancement of AChR clustering. We conclude that ZNS enhances agrin-dependent AChR-clustering by upregulating the Nrg1/ErbB signaling pathways in the presence of NMJs.
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34
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Fulceri F, Biagioni F, Limanaqi F, Busceti CL, Ryskalin L, Lenzi P, Fornai F. Ultrastructural characterization of peripheral denervation in a mouse model of Type III spinal muscular atrophy. J Neural Transm (Vienna) 2021; 128:771-791. [PMID: 33999256 PMCID: PMC8205903 DOI: 10.1007/s00702-021-02353-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 05/10/2021] [Indexed: 01/02/2023]
Abstract
Spinal muscular atrophy (SMA) is a heritable, autosomal recessive neuromuscular disorder characterized by a loss of the survival of motor neurons (SMN) protein, which leads to degeneration of lower motor neurons, and muscle atrophy. Despite SMA being nosographically classified as a motor neuron disease, recent advances indicate that peripheral alterations at the level of the neuromuscular junction (NMJ), involving the muscle, and axons of the sensory-motor system, occur early, and may even precede motor neuron loss. In the present study, we used a mouse model of slow progressive (type III) SMA, whereby the absence of the mouse SMN protein is compensated by the expression of two human genes (heterozygous SMN1A2G, and SMN2). This leads to late disease onset and prolonged survival, which allows for dissecting slow degenerative steps operating early in SMA pathogenesis. In this purely morphological study carried out at transmission electron microscopy, we extend the examination of motor neurons and proximal axons towards peripheral components, including distal axons, muscle fibers, and also muscle spindles. We document remarkable ultrastructural alterations being consistent with early peripheral denervation in SMA, which may shift the ultimate anatomical target in neuromuscular disease from the spinal cord towards the muscle. This concerns mostly mitochondrial alterations within distal axons and muscle, which are quantified here through ultrastructural morphometry. The present study is expected to provide a deeper knowledge of early pathogenic mechanisms in SMA.
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Affiliation(s)
- Federica Fulceri
- Department of Clinical and Experimental Medicine, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | | | - Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Carla L Busceti
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077, Pozzilli, IS, Italy
| | - Larisa Ryskalin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Paola Lenzi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | - Francesco Fornai
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077, Pozzilli, IS, Italy. .,Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy.
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35
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Nicolau S, Waldrop MA, Connolly AM, Mendell JR. Spinal Muscular Atrophy. Semin Pediatr Neurol 2021; 37:100878. [PMID: 33892848 DOI: 10.1016/j.spen.2021.100878] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/07/2020] [Accepted: 12/07/2020] [Indexed: 02/07/2023]
Abstract
Spinal muscular atrophy is one of the most common neuromuscular disorders of childhood and has high morbidity and mortality. Three different disease-modifying treatments were introduced in the last 4 years: nusinersen, onasemnogene abeparvovec, and risdiplam. These agents have demonstrated safety and efficacy, but their long-term benefits require further study. Newborn screening programs are enabling earlier diagnosis and treatment and better outcomes, but respiratory care and other supportive measures retain a key role in the management of spinal muscular atrophy. Ongoing efforts seek to optimize gene therapy vectors, explore new therapeutic targets beyond motor neurons, and evaluate the role of combination therapy.
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Affiliation(s)
- Stefan Nicolau
- Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH.
| | - Megan A Waldrop
- Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH; Departments of Pediatrics and Neurology, Ohio State University, Columbus, OH
| | - Anne M Connolly
- Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH; Departments of Pediatrics and Neurology, Ohio State University, Columbus, OH
| | - Jerry R Mendell
- Center for Gene Therapy, The Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH; Departments of Pediatrics and Neurology, Ohio State University, Columbus, OH
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36
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Yang S, Lim KH, Kim SH, Joo JY. Molecular landscape of long noncoding RNAs in brain disorders. Mol Psychiatry 2021; 26:1060-1074. [PMID: 33173194 DOI: 10.1038/s41380-020-00947-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/28/2020] [Accepted: 10/27/2020] [Indexed: 02/08/2023]
Abstract
According to current paradigms, various risk factors, such as genetic mutations, oxidative stress, neural network dysfunction, and abnormal protein degradation, contribute to the progression of brain disorders. Through the cooperation of gene transcripts in biological processes, the study of noncoding RNAs can lead to insights into the cause and treatment of brain disorders. Recently, long noncoding RNAs (lncRNAs) which are longer than 200 nucleotides in length have been suggested as key factors in various brain disorders. Accumulating evidence suggests the potential of lncRNAs as diagnostic or prognostic biomarkers and therapeutic targets. High-throughput screening-based sequencing has been instrumental in identification of lncRNAs that demand new approaches to understanding the progression of brain disorders. In this review, we discuss the recent progress in the study of lncRNAs, and addresses the pathogenesis of brain disorders that involve lncRNAs and describes the associations of lncRNAs with neurodegenerative disorders such as Alzheimer disease (AD), Parkinson disease (PD), and neurodevelopmental disorders. We also discuss potential targets of lncRNAs and their promise as novel therapeutics and biomarkers in brain disorders.
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Affiliation(s)
- Sumin Yang
- Neurodegenerative Disease Research Group, Korea Brain Research Institute, Daegu, 41062, Republic of Korea
| | - Key-Hwan Lim
- Neurodegenerative Disease Research Group, Korea Brain Research Institute, Daegu, 41062, Republic of Korea
| | - Sung-Hyun Kim
- Neurodegenerative Disease Research Group, Korea Brain Research Institute, Daegu, 41062, Republic of Korea
| | - Jae-Yeol Joo
- Neurodegenerative Disease Research Group, Korea Brain Research Institute, Daegu, 41062, Republic of Korea.
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37
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Jafar-nejad P, Powers B, Soriano A, Zhao H, Norris DA, Matson J, DeBrosse-Serra B, Watson J, Narayanan P, Chun S, Mazur C, Kordasiewicz H, Swayze EE, Rigo F. The atlas of RNase H antisense oligonucleotide distribution and activity in the CNS of rodents and non-human primates following central administration. Nucleic Acids Res 2021; 49:657-673. [PMID: 33367834 PMCID: PMC7826274 DOI: 10.1093/nar/gkaa1235] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 11/23/2020] [Accepted: 12/22/2020] [Indexed: 12/14/2022] Open
Abstract
Antisense oligonucleotides (ASOs) have emerged as a new class of drugs to treat a wide range of diseases, including neurological indications. Spinraza, an ASO that modulates splicing of SMN2 RNA, has shown profound disease modifying effects in Spinal Muscular Atrophy (SMA) patients, energizing efforts to develop ASOs for other neurological diseases. While SMA specifically affects spinal motor neurons, other neurological diseases affect different central nervous system (CNS) regions, neuronal and non-neuronal cells. Therefore, it is important to characterize ASO distribution and activity in all major CNS structures and cell types to have a better understanding of which neurological diseases are amenable to ASO therapy. Here we present for the first time the atlas of ASO distribution and activity in the CNS of mice, rats, and non-human primates (NHP), species commonly used in preclinical therapeutic development. Following central administration of an ASO to rodents, we observe widespread distribution and target RNA reduction throughout the CNS in neurons, oligodendrocytes, astrocytes and microglia. This is also the case in NHP, despite a larger CNS volume and more complex neuroarchitecture. Our results demonstrate that ASO drugs are well suited for treating a wide range of neurological diseases for which no effective treatments are available.
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Affiliation(s)
| | - Berit Powers
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | | | - Hien Zhao
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | | | - John Matson
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | | | - Jamie Watson
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | | | - Seung J Chun
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | - Curt Mazur
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
| | | | | | - Frank Rigo
- Ionis Pharmaceuticals Inc. Carlsbad, CA 92010, USA
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38
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Volpe JJ. Infantile spinal muscular atrophy - the potential for cure of a fatal disease. J Neonatal Perinatal Med 2021; 14:153-157. [PMID: 33459670 PMCID: PMC8075397 DOI: 10.3233/npm-200680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- J J Volpe
- Department of Neurology, Harvard Medical School, Boston, MA, USA.,Department of Pediatric Newborn Medicine, Harvard Medical School, Boston, MA, USA
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39
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Tharaneetharan A, Cole M, Norman B, Romero NC, Wooltorton JRA, Harrington MA, Sun J. Functional Abnormalities of Cerebellum and Motor Cortex in Spinal Muscular Atrophy Mice. Neuroscience 2020; 452:78-97. [PMID: 33212215 DOI: 10.1016/j.neuroscience.2020.10.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 10/23/2020] [Accepted: 10/28/2020] [Indexed: 11/26/2022]
Abstract
Spinal muscular atrophy (SMA) is a devastating genetic neuromuscular disease. Diffuse neuropathology has been reported in SMA patients and mouse models, however, functional changes in brain regions have not been studied. In the SMNΔ7 mouse model, we identified three types of differences in neuronal function in the cerebellum and motor cortex from two age groups: P7-9 (P7) and P11-14 (P11). Microelectrode array studies revealed significantly lower spontaneous firing and network activity in the cerebellum of SMA mice in both age groups, but it was more profound in the P11 group. In the motor cortex, however, neural activity was not different in either age group. Whole-cell patch-clamp was used to study the function of output neurons in both brain regions. In cerebellar Purkinje cells (PCs) of SMA mice, the input resistance was larger at P7, while capacitance was smaller at P11. In the motor cortex, no difference was observed in the passive membrane properties of layer V pyramidal neurons (PN5s). The action potential threshold of both types of output neurons was depolarized in the P11 group. We also observed lower spontaneous excitatory and inhibitory synaptic activity in PN5s and PCs respectively from P11 SMA mice. Overall, these differences suggest functional alterations in the neural network in these motor regions that change during development. Our results also suggest that neuronal dysfunction in these brain regions may contribute to the pathology of SMA. Comprehensive treatment strategies may consider motor regions outside of the spinal cord for better outcomes.
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Affiliation(s)
- Arumugarajah Tharaneetharan
- Delaware Center for Neuroscience Research, Department of Biological Sciences, Delaware State University, Dover, DE, USA
| | - Madison Cole
- Department of Psychology, Washington College, Chestertown, MD, USA
| | - Brandon Norman
- Department of Biology, Salisbury University, Salisbury, MD, USA
| | - Nayeli C Romero
- Department of Agriculture and Natural Science, Delaware State University, Dover, DE, USA
| | - Julian R A Wooltorton
- Delaware Center for Neuroscience Research, Department of Biological Sciences, Delaware State University, Dover, DE, USA
| | - Melissa A Harrington
- Delaware Center for Neuroscience Research, Department of Biological Sciences, Delaware State University, Dover, DE, USA
| | - Jianli Sun
- Delaware Center for Neuroscience Research, Department of Biological Sciences, Delaware State University, Dover, DE, USA.
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40
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Li A, Yi J, Li X, Zhou J. Physiological Ca 2+ Transients Versus Pathological Steady-State Ca 2+ Elevation, Who Flips the ROS Coin in Skeletal Muscle Mitochondria. Front Physiol 2020; 11:595800. [PMID: 33192612 PMCID: PMC7642813 DOI: 10.3389/fphys.2020.595800] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/05/2020] [Indexed: 12/20/2022] Open
Abstract
Mitochondria are both the primary provider of ATP and the pivotal regulator of cell death, which are essential for physiological muscle activities. Ca2+ plays a multifaceted role in mitochondrial function. During muscle contraction, Ca2+ influx into mitochondria activates multiple enzymes related to tricarboxylic acid (TCA) cycle and oxidative phosphorylation, resulting in increased ATP synthesis to meet the energy demand. Pathophysiological conditions such as skeletal muscle denervation or unloading also lead to elevated Ca2+ levels inside mitochondria. However, the outcomes of this steady-state elevation of mitochondrial Ca2+ level include exacerbated reactive oxygen species (ROS) generation, sensitized opening of mitochondrial permeability transition pore (mPTP), induction of programmed cell death, and ultimately muscle atrophy. Previously, both acute and long-term endurance exercises have been reported to activate certain signaling pathways to counteract ROS production. Meanwhile, electrical stimulation is known to help prevent apoptosis and alleviate muscle atrophy in denervated animal models and patients with motor impairment. There are various mechanistic studies that focus on the excitation-transcription coupling framework to understand the beneficial role of exercise and electrical stimulation. Interestingly, a recent study has revealed an unexpected role of rapid mitochondrial Ca2+ transients in keeping mPTP at a closed state with reduced mitochondrial ROS production. This discovery motivated us to contribute this review article to inspire further discussion about the potential mechanisms underlying differential outcomes of physiological mitochondrial Ca2+ transients and pathological mitochondrial Ca2+ elevation in skeletal muscle ROS production.
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Affiliation(s)
- Ang Li
- Department of Kinesiology, College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
| | - Jianxun Yi
- Department of Kinesiology, College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
| | - Xuejun Li
- Department of Kinesiology, College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
| | - Jingsong Zhou
- Department of Kinesiology, College of Nursing and Health Innovation, The University of Texas at Arlington, Arlington, TX, United States
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41
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Nelvagal HR, Hurtado ML, Eaton SL, Kline RA, Lamont DJ, Sands MS, Wishart TM, Cooper JD. Comparative proteomic profiling reveals mechanisms for early spinal cord vulnerability in CLN1 disease. Sci Rep 2020; 10:15157. [PMID: 32938982 PMCID: PMC7495486 DOI: 10.1038/s41598-020-72075-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 08/26/2020] [Indexed: 01/11/2023] Open
Abstract
CLN1 disease is a fatal inherited neurodegenerative lysosomal storage disease of early childhood, caused by mutations in the CLN1 gene, which encodes the enzyme Palmitoyl protein thioesterase-1 (PPT-1). We recently found significant spinal pathology in Ppt1-deficient (Ppt1−/−) mice and human CLN1 disease that contributes to clinical outcome and precedes the onset of brain pathology. Here, we quantified this spinal pathology at 3 and 7 months of age revealing significant and progressive glial activation and vulnerability of spinal interneurons. Tandem mass tagged proteomic analysis of the spinal cord of Ppt1−/−and control mice at these timepoints revealed a significant neuroimmune response and changes in mitochondrial function, cell-signalling pathways and developmental processes. Comparing proteomic changes in the spinal cord and cortex at 3 months revealed many similarly affected processes, except the inflammatory response. These proteomic and pathological data from this largely unexplored region of the CNS may help explain the limited success of previous brain-directed therapies. These data also fundamentally change our understanding of the progressive, site-specific nature of CLN1 disease pathogenesis, and highlight the importance of the neuroimmune response. This should greatly impact our approach to the timing and targeting of future therapeutic trials for this and similar disorders.
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Affiliation(s)
- Hemanth R Nelvagal
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA.,Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Maica Llavero Hurtado
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Samantha L Eaton
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Rachel A Kline
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Douglas J Lamont
- FingerPrints Proteomics Facility, College of Life Sciences, University of Dundee, Dundee, UK
| | - Mark S Sands
- Department of Genetics, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA.,Department of Medicine, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA
| | - Thomas M Wishart
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK
| | - Jonathan D Cooper
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA. .,Department of Genetics, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA. .,Department of Neurology, Washington University in St Louis, School of Medicine, 660 S Euclid Ave, St Louis, MO, 63110, USA. .,Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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42
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Li A, Zhou J, Widelitz RB, Chow RH, Chuong CM. Integrating Bioelectrical Currents and Ca 2+ Signaling with Biochemical Signaling in Development and Pathogenesis. Bioelectricity 2020; 2:210-220. [PMID: 34476353 PMCID: PMC8370337 DOI: 10.1089/bioe.2020.0001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Roles of bioelectrical signals are increasingly recognized in excitable and nonexcitable non-neural tissues. Diverse ion-selective channels, pumps, and gap junctions participate in bioelectrical signaling, including those transporting calcium ions (Ca2+). Ca2+ is the most versatile transported ion, because it serves as an electrical charge carrier and a biochemical regulator for multiple molecular binding, enzyme, and transcription activities. We aspire to learn how bioelectrical signals crosstalk to biochemical/biomechanical signals. In this study, we review four recent studies showing how bioelectrical currents and Ca2+ signaling affect collective dermal cell migration during feather bud elongation, affect chondrogenic differentiation in limb development, couple with mechanical tension in aligning gut smooth muscle, and affect mitochondrial function and skeletal muscle atrophy. We observe bioelectrical signals involved in several developmental and pathological conditions in chickens and mice at multiple spatial scales: cellular, cellular collective, and subcellular. These examples inspire novel concept and approaches for future basic and translational studies.
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Affiliation(s)
- Ang Li
- Department of Kinesiology, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, Texas, USA
| | - Jingsong Zhou
- Department of Kinesiology, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, Texas, USA
| | - Randall B. Widelitz
- Department of Pathology and Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Robert H. Chow
- Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Cheng-Ming Chuong
- Department of Pathology and Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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43
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Abstract
RNA-binding proteins are a critical group of multifunctional proteins that precisely regulate all aspects of gene expression, from alternative splicing to mRNA trafficking, stability, and translation. Converging evidence highlights aberrant RNA metabolism as a common pathogenic mechanism in several neurodevelopmental and neurodegenerative diseases. However, dysregulation of disease-linked RNA-binding proteins results in widespread, often tissue-specific and/or pleiotropic effects on the transcriptome, making it challenging to determine the underlying cellular and molecular mechanisms that contribute to disease pathogenesis. Understanding how splicing misregulation as well as alterations of mRNA stability and localization impact the activity and function of neuronal proteins is fundamental to addressing neurodevelopmental defects and synaptic dysfunction in disease. Here we highlight recent exciting studies that use high-throughput transcriptomic analysis and advanced genetic, cell biological, and imaging approaches to dissect the role of disease-linked RNA-binding proteins on different RNA processing steps. We focus specifically on efforts to elucidate the functional consequences of aberrant RNA processing on neuronal morphology, synaptic activity and plasticity in development and disease. We also consider new areas of investigation that will elucidate the molecular mechanisms RNA-binding proteins use to achieve spatiotemporal control of gene expression for neuronal homeostasis and plasticity.
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Affiliation(s)
- Shavanie Prashad
- Department of Pathology, Yale University School of Medicine, Yale University, New Haven, CT, USA.,Experimental Pathology Graduate Group, Yale University School of Medicine, Yale University, New Haven, CT, USA
| | - Pallavi P Gopal
- Department of Pathology, Yale University School of Medicine, Yale University, New Haven, CT, USA.,Experimental Pathology Graduate Group, Yale University School of Medicine, Yale University, New Haven, CT, USA.,Yale Center for RNA Science and Medicine, Yale University School of Medicine, Yale University, New Haven, CT, USA
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44
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Chang Y, Kim J, Park H, Choi H, Kim J. Modelling neurodegenerative diseases with 3D brain organoids. Biol Rev Camb Philos Soc 2020; 95:1497-1509. [PMID: 32568450 DOI: 10.1111/brv.12626] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 05/25/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023]
Abstract
Neurodegenerative diseases are incurable and debilitating conditions characterized by the deterioration of brain function. Most brain disease models rely on human post-mortem brain tissue, non-human primate tissue, or in vitro two-dimensional (2D) experiments. Resource limitations and the complexity of the human brain are some of the reasons that make suitable human neurodegenerative disease models inaccessible. However, recently developed three-dimensional (3D) brain organoids derived from pluripotent stem cells (PSCs), including embryonic stem cells and induced PSCs, may provide suitable models for the study of the pathological features of neurodegenerative diseases. In this review, we provide an overview of existing 3D brain organoid models and discuss recent advances in organoid technology that have increased our understanding of brain development. Moreover, we explain how 3D organoid models recapitulate aspects of specific neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease, and explore the utility of these models, for therapeutic applications.
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Affiliation(s)
- Yujung Chang
- Department of Biomedical Engineering, Dongguk University, Seoul, 04620, Republic of Korea
| | - Junyeop Kim
- Department of Biomedical Engineering, Dongguk University, Seoul, 04620, Republic of Korea
| | - Hanseul Park
- Department of Biomedical Engineering, Dongguk University, Seoul, 04620, Republic of Korea
| | - Hwan Choi
- Department of Biomedical Engineering, Dongguk University, Seoul, 04620, Republic of Korea
| | - Jongpil Kim
- Department of Biomedical Engineering, Dongguk University, Seoul, 04620, Republic of Korea.,Department of Chemistry, Dongguk University, Seoul, 04620, Republic of Korea
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Villalón E, Kline RA, Smith CE, Lorson ZC, Osman EY, O'Day S, Murray LM, Lorson CL. AAV9-Stathmin1 gene delivery improves disease phenotype in an intermediate mouse model of spinal muscular atrophy. Hum Mol Genet 2020; 28:3742-3754. [PMID: 31363739 DOI: 10.1093/hmg/ddz188] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/12/2019] [Accepted: 07/23/2019] [Indexed: 02/06/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a devastating infantile genetic disorder caused by the loss of survival motor neuron (SMN) protein that leads to premature death due to loss of motor neurons and muscle atrophy. The approval of an antisense oligonucleotide therapy for SMA was an important milestone in SMA research; however, effective next-generation therapeutics will likely require combinatorial SMN-dependent therapeutics and SMN-independent disease modifiers. A recent cross-disease transcriptomic analysis identified Stathmin-1 (STMN1), a tubulin-depolymerizing protein, as a potential disease modifier across different motor neuron diseases, including SMA. Here, we investigated whether viral-based delivery of STMN1 decreased disease severity in a well-characterized SMA mouse model. Intracerebroventricular delivery of scAAV9-STMN1 in SMA mice at P2 significantly increased survival and weight gain compared to untreated SMA mice without elevating Smn levels. scAAV9-STMN1 improved important hallmarks of disease, including motor function, NMJ pathology and motor neuron cell preservation. Furthermore, scAAV9-STMN1 treatment restored microtubule networks and tubulin expression without affecting tubulin stability. Our results show that scAAV9-STMN1 treatment improves SMA pathology possibly by increasing microtubule turnover leading to restored levels of stable microtubules. Overall, these data demonstrate that STMN1 can significantly reduce the SMA phenotype independent of restoring SMN protein and highlight the importance of developing SMN-independent therapeutics for the treatment of SMA.
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Affiliation(s)
- E Villalón
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - R A Kline
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - C E Smith
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Z C Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - E Y Osman
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - S O'Day
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - L M Murray
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
- Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
| | - C L Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
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Sapaly D, Delers P, Coridon J, Salman B, Letourneur F, Dumont F, Lefebvre S. The Small-Molecule Flunarizine in Spinal Muscular Atrophy Patient Fibroblasts Impacts on the Gemin Components of the SMN Complex and TDP43, an RNA-Binding Protein Relevant to Motor Neuron Diseases. Front Mol Biosci 2020; 7:55. [PMID: 32363199 PMCID: PMC7181958 DOI: 10.3389/fmolb.2020.00055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/18/2020] [Indexed: 01/01/2023] Open
Abstract
The motor neurodegenerative disease spinal muscular atrophy (SMA) is caused by alterations of the survival motor neuron 1 (SMN1) gene involved in RNA metabolism. Although the disease mechanisms are not completely elucidated, SMN protein deficiency leads to abnormal small nuclear ribonucleoproteins (snRNPs) assembly responsible for widespread splicing defects. SMN protein localizes in nuclear bodies that are lost in SMA and adult onset amyotrophic lateral sclerosis (ALS) patient cells harboring TDP-43 or FUS/TLS mutations. We previously reported that flunarizine recruits SMN into nuclear bodies and improves the phenotype of an SMA mouse model. However, the precise mode of action remains elusive. Here, a marked reduction of the integral components of the SMN complex is observed in severe SMA patient fibroblast cells. We show that flunarizine increases the protein levels of a subset of components of the SMN-Gemins complex, Gemins2-4, and markedly reduces the RNA and protein levels of the pro-oxydant thioredoxin-interacting protein (TXNIP) encoded by an mRNA target of Gemin5. We further show that SMN deficiency causes a dissociation of the localization of the SMN complex components from the same nuclear bodies. The accumulation of TDP-43 in SMN-positive nuclear bodies is also perturbed in SMA cells. Notably, TDP-43 is found to co-localize with SMN in nuclear bodies of flunarizine-treated SMA cells. Our findings indicate that flunarizine reverses cellular changes caused by SMN deficiency in SMA cells and further support the view of a common pathway in RNA metabolism underlying infantile and adult motor neuron diseases.
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Affiliation(s)
- Delphine Sapaly
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, Campus Saint-Germain-des-Prés, Université de Paris, Paris, France
| | - Perrine Delers
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, Campus Saint-Germain-des-Prés, Université de Paris, Paris, France
| | - Jennifer Coridon
- BioMedTech Facilities INSERM US36 - CNRS UMS 2009, Campus Saint-Germain-des-Prés, Université de Paris, Paris, France
| | - Badih Salman
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, Campus Saint-Germain-des-Prés, Université de Paris, Paris, France
| | | | - Florent Dumont
- Genom'ic Platform, INSERM U1016, Institut Cochin, Paris, France
| | - Suzie Lefebvre
- INSERM UMR-S 1124, Toxicité Environnementale, Cibles Thérapeutiques, Signalisation Cellulaire et Biomarqueurs, Campus Saint-Germain-des-Prés, Université de Paris, Paris, France
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Abstract
Spinal muscular atrophy (SMA) is the most common genetic disease leading to infant mortality. This neuro-muscular disorder is caused by the loss or mutation of the telomeric copy of the 'survival of motor neuron' (Smn) gene, termed SMN1. Loss of SMN1 leads to reduced SMN protein levels, inducing degeneration of motor neurons (MN) and progressive muscle weakness and atrophy. Gene therapy, consisting of reintroducing SMN1 in the MNs, is an attractive approach for SMA. We showed the most efficient rescue of SMA mice to date after a single intravenous injection of an AAV9 expressing SMN1, highlighting the considerable potential of this method for the treatment of human SMA. Recently, a startup led by the Dr Kaspar decided to test this experimental approach in children with SMA type 1. Dr Mendell, in charge of this clinical project, showed a very significant increase of the lifespan and motor function of the patients (until 4 years) after a single injection of AAV9-SMN1 (named ZolgenSMA®) into an arm or leg vein. This gene therapy treatment obtained a marketing authorization by the FDA in May 24 and is now the first efficient therapy for neuromuscular disease.
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Affiliation(s)
- Martine Barkats
- Groupe Biothérapies des maladies du motoneurone, Centre de Recherche en Myologie, Sorbonne Université - UMRS974 Inserm - Institut de Myologie, Faculté de Médecine, 105 boulevard de l'Hôpital, 75013 Paris, France
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48
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Hensel N, Kubinski S, Claus P. The Need for SMN-Independent Treatments of Spinal Muscular Atrophy (SMA) to Complement SMN-Enhancing Drugs. Front Neurol 2020; 11:45. [PMID: 32117013 PMCID: PMC7009174 DOI: 10.3389/fneur.2020.00045] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 01/13/2020] [Indexed: 12/25/2022] Open
Abstract
Spinal Muscular Atrophy (SMA) is monogenic motoneuron disease caused by low levels of the Survival of Motoneuron protein (SMN). Recently, two different drugs were approved for the treatment of the disease. The antisense oligonucleotide Nusinersen/Spinraza® and the gene replacement therapy Onasemnogene Abeparvovec/Zolgensma® both enhance SMN levels. These treatments result in impressive benefits for the patients. However, there is a significant number of non-responders and an intervention delay has a strong negative impact on the efficacy. Obviously, later stages of motoneuron degeneration cannot be reversed by SMN-restoration. Therefore, complementary, SMN-independent strategies are needed which are able to address such SMN-irreversible degenerative processes. Those are defined as pathological alterations which are not reversed by SMN-restoration for a given dose and intervention delay. It is crucial to tailor SMN-independent approaches to the novel clinical situation with SMN-restoring treatments. On the molecular level, such SMN-irreversible changes become manifest in altered signaling modules as described by molecular systems biology. Based on our current knowledge about altered signaling, we introduce a network approach for an informed decision for the most potent SMN-independent treatment targets. Finally, we present recommendations for the identification of novel treatments which can be combined with SMN-restoring drugs.
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Affiliation(s)
- Niko Hensel
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Center of Systems Neuroscience (ZSN), Hannover, Germany
| | - Sabrina Kubinski
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Center of Systems Neuroscience (ZSN), Hannover, Germany
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Center of Systems Neuroscience (ZSN), Hannover, Germany
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Wirth B, Karakaya M, Kye MJ, Mendoza-Ferreira N. Twenty-Five Years of Spinal Muscular Atrophy Research: From Phenotype to Genotype to Therapy, and What Comes Next. Annu Rev Genomics Hum Genet 2020; 21:231-261. [PMID: 32004094 DOI: 10.1146/annurev-genom-102319-103602] [Citation(s) in RCA: 129] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Twenty-five years ago, the underlying genetic cause for one of the most common and devastating inherited diseases in humans, spinal muscular atrophy (SMA), was identified. Homozygous deletions or, rarely, subtle mutations of SMN1 cause SMA, and the copy number of the nearly identical copy gene SMN2 inversely correlates with disease severity. SMA has become a paradigm and a prime example of a monogenic neurological disorder that can be efficiently ameliorated or nearly cured by novel therapeutic strategies, such as antisense oligonucleotide or gene replacement therapy. These therapies enable infants to survive who might otherwise have died before the age of two and allow individuals who have never been able to sit or walk to do both. The major milestones on the road to these therapies were to understand the genetic cause and splice regulation of SMN genes, the disease's phenotype-genotype variability, the function of the protein and the main affected cellular pathways and tissues, the disease's pathophysiology through research on animal models, the windows of opportunity for efficient treatment, and how and when to treat patients most effectively.This review aims to bridge our knowledge from phenotype to genotype to therapy, not only highlighting the significant advances so far but also speculating about the future of SMA screening and treatment.
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Affiliation(s)
- Brunhilde Wirth
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Mert Karakaya
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Min Jeong Kye
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Natalia Mendoza-Ferreira
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
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50
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Li C, Geng Y, Zhu X, Zhang L, Hong Z, Guo X, Xia C. The prevalence of spinal muscular atrophy carrier in China: Evidences from epidemiological surveys. Medicine (Baltimore) 2020; 99:e18975. [PMID: 32000428 PMCID: PMC7004774 DOI: 10.1097/md.0000000000018975] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION Spinal muscular atrophy (SMA) was the second most fatal autosomal recessive hereditary disease in clinic. There had been no detailed study to characterize the prevalence of SMA carrier among people in China. So, we conducted a systematic review and meta-analysis to obtain a reliable estimation of the prevalence of SMA carrier to characterize its epidemiology for the first time. METHODS We systematically searched for articles in kinds of important electronic databases, including PubMed, Embase, Wanfang Database and China National Knowledge Infrastructure (CNKI) to identify all relevant literatures about carrier rates of SMA in China. The prevalence was performed by forest plot choosing random effect models. The publication bias was evaluated by means of funnel plots and Egger test. The sensitivity analysis was carried out by the method of omitting any literature at a time. Combined with the results of subgroup analysis, the source of heterogeneity was also discussed absolutely. RESULTS A total of 10 studies published between 2005 and 2016 were included in our analysis at last. The sample size ranged from 264 to 107,611 in included studies. The random effect models of meta-analysis showed that the overall carrier rate of SMA was 2.0% (95% confidence interval [CI], 1.7%-2.3%) in a heterogeneous set of studies (I = 64%). There was a gradual rise trend observed in the SMA carrier rate during the study period. The funnel plots and Egger test (Coef = 0.02, t = -0.45, P = .667 > .05) showed no obvious potential risk of publication bias. CONCLUSION The overall carrying rate of SMA was high as 2.0% and may be on a slow upward trend. So it was recommended that the countries should take active and effective measures to roll out routine prenatal screening and health genetic counseling for SMA as early as possible. What is more, further studies also need to be conducted to explore the etiology and epidemic factors of SMA to better control the risk of this common birth defect.
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Affiliation(s)
- Chao Li
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
| | - Yanfang Geng
- Department of Science & Education Division, Huangpu, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xiaodan Zhu
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
| | - Linghua Zhang
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
| | - Zhantong Hong
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
| | - Xiaoling Guo
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
| | - Chenglai Xia
- Foshan Fetal Medicine Research Institute, Foshan Women and Children Hospital Affiliated to Southern Medical University, Foshan
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