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Rzepnikowska W, Kaminska J, Kochański A. The molecular mechanisms that underlie IGHMBP2-related diseases. Neuropathol Appl Neurobiol 2024; 50:e13005. [PMID: 39119929 DOI: 10.1111/nan.13005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 07/18/2024] [Accepted: 07/20/2024] [Indexed: 08/10/2024]
Abstract
Immunoglobulin Mu-binding protein 2 (IGHMBP2) pathogenic variants result in the fatal, neurodegenerative disease spinal muscular atrophy with respiratory distress type 1 (SMARD1) and the milder, Charcot-Marie-Tooth (CMT) type 2S (CMT2S) neuropathy. More than 20 years after the link between IGHMBP2 and SMARD1 was revealed, and 10 years after the discovery of the association between IGHMBP2 and CMT2S, the pathogenic mechanism of these diseases is still not well defined. The discovery that IGHMBP2 functions as an RNA/DNA helicase was an important step, but it did not reveal the pathogenic mechanism. Helicases are enzymes that use ATP hydrolysis to catalyse the separation of nucleic acid strands. They are involved in numerous cellular processes, including DNA repair and transcription; RNA splicing, transport, editing and degradation; ribosome biogenesis; translation; telomere maintenance; and homologous recombination. IGHMBP2 appears to be a multifunctional factor involved in several cellular processes that regulate gene expression. It is difficult to determine which processes, when dysregulated, lead to pathology. Here, we summarise our current knowledge of the clinical presentation of IGHMBP2-related diseases. We also overview the available models, including yeast, mice and cells, which are used to study the function of IGHMBP2 and the pathogenesis of the related diseases. Further, we discuss the structure of the IGHMBP2 protein and its postulated roles in cellular functioning. Finally, we present potential anomalies that may result in the neurodegeneration observed in IGHMBP2-related disease and highlight the most prominent ones.
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Affiliation(s)
- Weronika Rzepnikowska
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw, 02-106, Poland
| | - Joanna Kaminska
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, Warsaw, 02-106, Poland
| | - Andrzej Kochański
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw, 02-106, Poland
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Schneider C, Bohnsack KE. Caught in the act-Visualizing ribonucleases during eukaryotic ribosome assembly. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1766. [PMID: 36254602 DOI: 10.1002/wrna.1766] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/22/2022] [Accepted: 09/24/2022] [Indexed: 07/20/2023]
Abstract
Ribosomes are essential macromolecular machines responsible for translating the genetic information encoded in mRNAs into proteins. Ribosomes are composed of ribosomal RNAs and proteins (rRNAs and RPs) and the rRNAs fulfill both catalytic and architectural functions. Excision of the mature eukaryotic rRNAs from their precursor transcript is achieved through a complex series of endoribonucleolytic cleavages and exoribonucleolytic processing steps that are precisely coordinated with other aspects of ribosome assembly. Many ribonucleases involved in pre-rRNA processing have been identified and pre-rRNA processing pathways are relatively well defined. However, momentous advances in cryo-electron microscopy have recently enabled structural snapshots of various pre-ribosomal particles from budding yeast (Saccharomyces cerevisiae) and human cells to be captured and, excitingly, these structures not only allow pre-rRNAs to be observed before and after cleavage events, but also enable ribonucleases to be visualized on their target RNAs. These structural views of pre-rRNA processing in action allow a new layer of understanding of rRNA maturation and how it is coordinated with other aspects of ribosome assembly. They illuminate mechanisms of target recognition by the diverse ribonucleases involved and reveal how the cleavage/processing activities of these enzymes are regulated. In this review, we discuss the new insights into pre-rRNA processing gained by structural analyses and the growing understanding of the mechanisms of ribonuclease regulation. This article is categorized under: Translation > Ribosome Biogenesis RNA Processing > rRNA Processing.
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Affiliation(s)
- Claudia Schneider
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Katherine E Bohnsack
- Department of Molecular Biology, University Medical Center Göttingen, Göttingen, Germany
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3
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Cutrupi AN, Narayanan RK, Perez-Siles G, Grosz BR, Lai K, Boyling A, Ellis M, Lin RCY, Neumann B, Mao D, Uesugi M, Nicholson GA, Vucic S, Saporta MA, Kennerson ML. Novel gene-intergenic fusion involving ubiquitin E3 ligase UBE3C causes distal hereditary motor neuropathy. Brain 2023; 146:880-897. [PMID: 36380488 PMCID: PMC9976978 DOI: 10.1093/brain/awac424] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/13/2022] [Accepted: 10/30/2022] [Indexed: 11/17/2022] Open
Abstract
Distal hereditary motor neuropathies (dHMNs) are a group of inherited diseases involving the progressive, length-dependent axonal degeneration of the lower motor neurons. There are currently 29 reported causative genes and four disease loci implicated in dHMN. Despite the high genetic heterogeneity, mutations in the known genes account for less than 20% of dHMN cases, with the mutations identified predominantly being point mutations or indels. We have expanded the spectrum of dHMN mutations with the identification of a 1.35 Mb complex structural variation (SV) causing a form of autosomal dominant dHMN (DHMN1 OMIM %182906). Given the complex nature of SV mutations and the importance of studying pathogenic mechanisms in a neuronal setting, we generated a patient-derived DHMN1 motor neuron model harbouring the 1.35 Mb complex insertion. The DHMN1 complex insertion creates a duplicated copy of the first 10 exons of the ubiquitin-protein E3 ligase gene (UBE3C) and forms a novel gene-intergenic fusion sense transcript by incorporating a terminal pseudo-exon from intergenic sequence within the DHMN1 locus. The UBE3C intergenic fusion (UBE3C-IF) transcript does not undergo nonsense-mediated decay and results in a significant reduction of wild-type full-length UBE3C (UBE3C-WT) protein levels in DHMN1 iPSC-derived motor neurons. An engineered transgenic Caenorhabditis elegans model expressing the UBE3C-IF transcript in GABA-ergic motor neurons shows neuronal synaptic transmission deficits. Furthermore, the transgenic animals are susceptible to heat stress, which may implicate defective protein homeostasis underlying DHMN1 pathogenesis. Identification of the novel UBE3C-IF gene-intergenic fusion transcript in motor neurons highlights a potential new disease mechanism underlying axonal and motor neuron degeneration. These complementary models serve as a powerful paradigm for studying the DHMN1 complex SV and an invaluable tool for defining therapeutic targets for DHMN1.
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Affiliation(s)
- Anthony N Cutrupi
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Ramesh K Narayanan
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Gonzalo Perez-Siles
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Bianca R Grosz
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Kaitao Lai
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Ancestry and Health Genomics Laboratory, Charles Perkins Centre, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Alexandra Boyling
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Melina Ellis
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Ruby C Y Lin
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
- Centre for Infectious Diseases and Microbiology, Westmead Institute for Medical Research, Sydney, NSW 2145, Australia
| | - Brent Neumann
- Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology, Monash University, Melbourne, VIC 3800, Australia
| | - Di Mao
- Institute for Integrated Cell-Material Sciences and Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Motonari Uesugi
- Institute for Integrated Cell-Material Sciences and Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan
| | - Garth A Nicholson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Molecular Medicine Laboratory, Concord Repatriation General Hospital, Sydney, NSW 2139, Australia
| | - Steve Vucic
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
- Brain and Nerve Research Centre, Concord Repatriation General Hospital, Sydney, NSW 2139, Australia
| | - Mario A Saporta
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Marina L Kennerson
- Northcott Neuroscience Laboratory, ANZAC Research Institute, Sydney, NSW 2139, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
- Molecular Medicine Laboratory, Concord Repatriation General Hospital, Sydney, NSW 2139, Australia
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Vadla GP, Ricardez Hernandez SM, Mao J, Garro-Kacher MO, Lorson ZC, Rice RP, Hansen SA, Lorson CL, Singh K, Lorson MA. ABT1 modifies SMARD1 pathology via interactions with IGHMBP2 and stimulation of ATPase and helicase activity. JCI Insight 2023; 8:e164608. [PMID: 36480289 PMCID: PMC9977310 DOI: 10.1172/jci.insight.164608] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022] Open
Abstract
SMA with respiratory distress type 1 (SMARD1) and Charcot-Marie-Tooth type 2S (CMT2S) are results of mutations in immunoglobulin mu DNA binding protein 2 (IGHMBP2). IGHMBP2 is a UPF1-like helicase with proposed roles in several cellular processes, including translation. This study examines activator of basal transcription 1 (ABT1), a modifier of SMARD1-nmd disease pathology. Microscale thermophoresis and dynamic light scattering demonstrate that IGHMBP2 and ABT1 proteins directly interact with high affinity. The association of ABT1 with IGHMBP2 significantly increases the ATPase and helicase activity as well as the processivity of IGHMBP2. The IGHMBP2/ABT1 complex interacts with the 47S pre-rRNA 5' external transcribed spacer and U3 small nucleolar RNA (snoRNA), suggesting that the IGHMBP2/ABT1 complex is important for pre-rRNA processing. Intracerebroventricular injection of scAAV9-Abt1 decreases FVB-Ighmbp2nmd/nmd disease pathology, significantly increases lifespan, and substantially decreases neuromuscular junction denervation. To our knowledge, ABT1 is the first disease-modifying gene identified for SMARD1. We provide a mechanism proposing that ABT1 decreases disease pathology in FVB-Ighmbp2nmd/nmd mutants by optimizing IGHMBP2 biochemical activity (ATPase and helicase activity). Our studies provide insight into SMARD1 pathogenesis, suggesting that ABT1 modifies IGHMBP2 activity as a means to regulate pre-rRNA processing.
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Affiliation(s)
- Gangadhar P. Vadla
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Sara M. Ricardez Hernandez
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Jiude Mao
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Mona O. Garro-Kacher
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Zachary C. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Ronin P. Rice
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Sarah A. Hansen
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Christian L. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Kamal Singh
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
| | - Monique A. Lorson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, and
- Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
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Respiratory phenotypes of neuromuscular diseases: A challenging issue for pediatricians. Pediatr Neonatol 2023; 64:109-118. [PMID: 36682912 DOI: 10.1016/j.pedneo.2022.09.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 08/25/2022] [Accepted: 09/21/2022] [Indexed: 01/05/2023] Open
Abstract
Neuromuscular disease (NMDs) encompass a heterogeneous group of genetic disorders, with respiratory problems of variable intensity and progression described at any pediatric age, from infancy to adolescence, and they are largely associated with significant lifelong morbidity and high mortality. Restriction of breathing, impaired gas exchange, decline of lung function and sleep disordered breathing progressively develop because of muscular weakness and culminate in respiratory failure. Depending on the disease progression, airways manifestations can take weeks to months or even years to evolve, thus depicting two major respiratory phenotypes, characterized by rapid or slow progression to respiratory failure. Assessing type and age at onset of airways problems and their evolution over time can support pediatricians in the diagnostic assessment of NMD. In addition, knowing the characteristics of patients' respiratory phenotype can increase the level of awareness among neonatologists, geneticists, neurologists, pulmonologists, nutritionists, and chest therapists, supporting them in the challenging task of the multidisciplinary medical care of patients. In this review we examine the issues related to the pediatric respiratory phenotypes of NMD and present a novel algorithm that can act as a guide for the diagnostic agenda and the key preventive or therapeutic interventions of airways manifestations. With prolonged survival of children with NMD, the advent of neuromuscular respiratory medicine, including accurate assessment of the respiratory phenotype, will help physicians to determine patients' prognoses and to design studies for the evaluation of new therapies.
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Zambon AA, Pini V, Bosco L, Falzone YM, Munot P, Muntoni F, Previtali SC. Early onset hereditary neuronopathies: an update on non-5q motor neuron diseases. Brain 2022; 146:806-822. [PMID: 36445400 PMCID: PMC9976982 DOI: 10.1093/brain/awac452] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/21/2022] [Accepted: 11/12/2022] [Indexed: 11/30/2022] Open
Abstract
Hereditary motor neuropathies (HMN) were first defined as a group of neuromuscular disorders characterized by lower motor neuron dysfunction, slowly progressive length-dependent distal muscle weakness and atrophy, without sensory involvement. Their cumulative estimated prevalence is 2.14/100 000 and, to date, around 30 causative genes have been identified with autosomal dominant, recessive,and X-linked inheritance. Despite the advances of next generation sequencing, more than 60% of patients with HMN remain genetically uncharacterized. Of note, we are increasingly aware of the broad range of phenotypes caused by pathogenic variants in the same gene and of the considerable clinical and genetic overlap between HMN and other conditions, such as Charcot-Marie-Tooth type 2 (axonal), spinal muscular atrophy with lower extremities predominance, neurogenic arthrogryposis multiplex congenita and juvenile amyotrophic lateral sclerosis. Considering that most HMN present during childhood, in this review we primarily aim to summarize key clinical features of paediatric forms, including recent data on novel phenotypes, to help guide differential diagnosis and genetic testing. Second, we describe newly identified causative genes and molecular mechanisms, and discuss how the discovery of these is changing the paradigm through which we approach this group of conditions.
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Affiliation(s)
- Alberto A Zambon
- Correspondence to: Alberto A. Zambon Neuromuscular Repair Unit InSpe and Division of Neuroscience IRCCS Ospedale San Raffaele, Milan, Italy E-mail:
| | - Veronica Pini
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital, London, WC1N 1EH, UK
| | - Luca Bosco
- Neuromuscular Repair Unit, Institute of Experimental Neurology (InSpe), Division of Neuroscience, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Yuri M Falzone
- Neuromuscular Repair Unit, Institute of Experimental Neurology (InSpe), Division of Neuroscience, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Pinki Munot
- NIHR Great Ormond Street Hospital Biomedical Research Centre, London, WC1N 1EH, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital, London, WC1N 1EH, UK,NIHR Great Ormond Street Hospital Biomedical Research Centre, London, WC1N 1EH, UK
| | - Stefano C Previtali
- Neuromuscular Repair Unit, Institute of Experimental Neurology (InSpe), Division of Neuroscience, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
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7
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Frasquet M, Sevilla T. Hereditary motor neuropathies. Curr Opin Neurol 2022; 35:562-570. [PMID: 35942667 DOI: 10.1097/wco.0000000000001087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Distal hereditary motor neuropathies (dHMN) are a clinically and genetically diverse group of disorders that are characterized by length-dependent axonal degeneration of lower motor neurons. In this review, we will provide an overview of dHMN, and we will correlate the distinct clinical subtypes with their causative genes, focusing on the most recent advances in the field. RECENT FINDINGS Despite the massive use of new-generation sequencing (NGS) and the discovery of new genes, only a third of dHMN patients receive a molecular diagnosis. Thanks to international cooperation between researchers, new genes have been implicated in dHMN, such as SORD and VWA1 . Mutations in SORD are the most frequent cause of autosomal recessive forms of dHMN. As a result of these findings, the potential benefits of some pharmacological compounds are being studied in cell and animal models, mainly targeting axonal transport and metabolic pathways. SUMMARY Despite the wide use of NGS, the diagnosis of dHMN remains a challenge. The low prevalence of dHMN makes international cooperation necessary in order to discover new genes and causal mechanisms. Genetic diagnosis of patients and identification of new pathomechanism are essential for the development of therapeutical clinical trials.
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Affiliation(s)
- Marina Frasquet
- Department of Neurology, Hospital Universitari Doctor Peset
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain
| | - Teresa Sevilla
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitari i Politècnic La Fe
- Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) Spain
- Universitat de València, Valencia, Spain
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Stembalska A, Rydzanicz M, Walas W, Gasperowicz P, Pollak A, Pienkowski VM, Biela M, Klaniewska M, Gamrot Z, Gronska E, Ploski R, Smigiel R. Severe Infantile Axonal Neuropathy with Respiratory Failure Caused by Novel Mutation in X-Linked LAS1L Gene. Genes (Basel) 2022; 13:genes13050725. [PMID: 35627110 PMCID: PMC9142081 DOI: 10.3390/genes13050725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/11/2022] [Accepted: 04/19/2022] [Indexed: 12/10/2022] Open
Abstract
LAS1L encodes a nucleolar ribosomal biogenesis protein and is also a component of the Five Friends of Methylated CHTOP (5FMC) complex. Mutations in the LAS1L gene can be associated with Wilson−Turner syndrome (WTS) and, much more rarely, severe infantile hypotonia with respiratory failure. Here, we present an eighteen-month old boy with a phenotype of spinal muscular atrophy with respiratory distress (SMARD). By applying WES, we identified a novel hemizygous synonymous variant in the LAS1L gene inherited from an unaffected mother (c.846G > C, p.Thr282=). We suggest that the identified variant impairs the RNA splicing process. Furthermore, we proved the absence of any coding regions by qPCR and sequencing cDNA using amplicon deep sequencing and Sanger sequencing methods. According to the SMARD phenotype, severe breathing problems causing respiratory insufficiency, hypotonia, and feeding difficulties were observed in our patient from the first days of life. Remarkably, our case is the second described patient with a SMARD-like phenotype due to a mutation in the LAS1L gene and the first with a variant impacting splicing.
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Affiliation(s)
| | - Małgorzata Rydzanicz
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
- Correspondence: (M.R.); (R.S.)
| | - Wojciech Walas
- Paediatric and Neonatal Intensive Care Unit, University Hospital in Opole, 45-401 Opole, Poland;
| | - Piotr Gasperowicz
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Agnieszka Pollak
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Victor Murcia Pienkowski
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
- MMG, Marseille Medical Genetics U1251, Aix Marseille University, 13385 Marseille, France
| | - Mateusz Biela
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
| | - Magdalena Klaniewska
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
| | - Zuzanna Gamrot
- Care and Therapy Unit for Mechanically Ventilated Children and Young People, 41-506 Chorzow, Poland; (Z.G.); (E.G.)
| | - Ewa Gronska
- Care and Therapy Unit for Mechanically Ventilated Children and Young People, 41-506 Chorzow, Poland; (Z.G.); (E.G.)
| | - Rafal Ploski
- Department of Medical Genetics, Medical University of Warsaw, 02-106 Warsaw, Poland; (P.G.); (A.P.); (V.M.P.); (R.P.)
| | - Robert Smigiel
- Department of Family and Paediatric Nursing, Medical University, 50-996 Wroclaw, Poland; (M.B.); (M.K.)
- Correspondence: (M.R.); (R.S.)
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9
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Rapid Onset of Neuromuscular Paralysis or Weakness. Crit Care Clin 2022; 38:413-428. [DOI: 10.1016/j.ccc.2021.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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10
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Rzepnikowska W, Kochański A. Models for IGHMBP2-associated diseases: an overview and a roadmap for the future. Neuromuscul Disord 2021; 31:1266-1278. [PMID: 34785121 DOI: 10.1016/j.nmd.2021.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/16/2021] [Accepted: 08/06/2021] [Indexed: 12/13/2022]
Abstract
Models are practical tools with which to establish the basic aspects of a diseases. They allow systematic research into the significance of mutations, of cellular and molecular pathomechanisms, of therapeutic options and of functions of diseases associated proteins. Thus, disease models are an integral part of the study of enigmatic proteins such as immunoglobulin mu-binding protein 2 (IGHMBP2). IGHMBP2 has been well defined as a helicase, however there is little known about its role in cellular processes. Notably, it is unclear why changes in such an abundant protein lead to specific neuronal disorders including spinal muscular atrophy with respiratory distress type 1 (SMARD1) and Charcot-Marie-Tooth type 2S (CMT2S). SMARD1 is caused by a loss of motor neurons in the spinal cord that results in muscle atrophy and is accompanied by rapid respiratory failure. In contrast, CMT2S manifests as a severe neuropathy, but typically without critical breathing problems. Here, we present the clinical manifestation of IGHMBP2 mutations, function of protein and models that may be used for the study of IGHMBP2-associated disorders. We highlight the strengths and weaknesses of specific models and discuss the orthologs of IGHMBP2 that are found in different systems with regard to their similarity to human IGHMBP2.
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Affiliation(s)
- Weronika Rzepnikowska
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw 02-106, Poland.
| | - Andrzej Kochański
- Neuromuscular Unit, Mossakowski Medical Research Institute Polish Academy of Sciences, Warsaw 02-106, Poland
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11
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Wu Z, Gong H, Zhang M, Tong X, Ai H, Xiao S, Perez-Enciso M, Yang B, Huang L. A worldwide map of swine short tandem repeats and their associations with evolutionary and environmental adaptations. Genet Sel Evol 2021; 53:39. [PMID: 33892623 PMCID: PMC8063339 DOI: 10.1186/s12711-021-00631-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 04/09/2021] [Indexed: 11/10/2022] Open
Abstract
Background Short tandem repeats (STRs) are genetic markers with a greater mutation rate than single nucleotide polymorphisms (SNPs) and are widely used in genetic studies and forensics. However, most studies in pigs have focused only on SNPs or on a limited number of STRs. Results This study screened 394 deep-sequenced genomes from 22 domesticated pig breeds/populations worldwide, wild boars from both Europe and Asia, and numerous outgroup Suidaes, and identified a set of 878,967 polymorphic STRs (pSTRs), which represents the largest repository of pSTRs in pigs to date. We found multiple lines of evidence that pSTRs in coding regions were affected by purifying selection. The enrichment of trinucleotide pSTRs in coding sequences (CDS), 5′UTR and H3K4me3 regions suggests that trinucleotide STRs serve as important components in the exons and promoters of the corresponding genes. We demonstrated that, compared to SNPs, pSTRs provide comparable or even greater accuracy in determining the breed identity of individuals. We identified pSTRs that showed significant population differentiation between domestic pigs and wild boars in Asia and Europe. We also observed that some pSTRs were significantly associated with environmental variables, such as average annual temperature or altitude of the originating sites of Chinese indigenous breeds, among which we identified loss-of-function and/or expanded STRs overlapping with genes such as AHR, LAS1L and PDK1. Finally, our results revealed that several pSTRs show stronger signals in domestic pig—wild boar differentiation or association with the analysed environmental variables than the flanking SNPs within a 100-kb window. Conclusions This study provides a genome-wide high-density map of pSTRs in diverse pig populations based on genome sequencing data, enabling a more comprehensive characterization of their roles in evolutionary and environmental adaptation. Supplementary Information The online version contains supplementary material available at 10.1186/s12711-021-00631-4.
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Affiliation(s)
- Zhongzi Wu
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Huanfa Gong
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Mingpeng Zhang
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Xinkai Tong
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Huashui Ai
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Shijun Xiao
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China
| | - Miguel Perez-Enciso
- Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Barcelona, Spain.,ICREA, Passeig de Lluís Companys 23, Barcelona, Spain
| | - Bin Yang
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China.
| | - Lusheng Huang
- State Key Laboratory for Pig Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang, China.
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12
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Pillon MC, Gordon J, Frazier MN, Stanley RE. HEPN RNases - an emerging class of functionally distinct RNA processing and degradation enzymes. Crit Rev Biochem Mol Biol 2021; 56:88-108. [PMID: 33349060 PMCID: PMC7856873 DOI: 10.1080/10409238.2020.1856769] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/06/2020] [Accepted: 11/24/2020] [Indexed: 10/22/2022]
Abstract
HEPN (Higher Eukaryotes and Prokaryotes Nucleotide-binding) RNases are an emerging class of functionally diverse RNA processing and degradation enzymes. Members are defined by a small α-helical bundle encompassing a short consensus RNase motif. HEPN dimerization is a universal requirement for RNase activation as the conserved RNase motifs are precisely positioned at the dimer interface to form a composite catalytic center. While the core HEPN fold is conserved, the organization surrounding the HEPN dimer can support large structural deviations that contribute to their specialized functions. HEPN RNases are conserved throughout evolution and include bacterial HEPN RNases such as CRISPR-Cas and toxin-antitoxin associated nucleases, as well as eukaryotic HEPN RNases that adopt large multi-component machines. Here we summarize the canonical elements of the growing HEPN RNase family and identify molecular features that influence RNase function and regulation. We explore similarities and differences between members of the HEPN RNase family and describe the current mechanisms for HEPN RNase activation and inhibition.
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Affiliation(s)
- Monica C. Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Jacob Gordon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Meredith N. Frazier
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E. Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
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13
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Ribosomopathies: New Therapeutic Perspectives. Cells 2020; 9:cells9092080. [PMID: 32932838 PMCID: PMC7564184 DOI: 10.3390/cells9092080] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/03/2020] [Accepted: 09/08/2020] [Indexed: 12/13/2022] Open
Abstract
Ribosomopathies are a group of rare diseases in which genetic mutations cause defects in either ribosome biogenesis or function, given specific phenotypes. Ribosomal proteins, and multiple other factors that are necessary for ribosome biogenesis (rRNA processing, assembly of subunits, export to cytoplasm), can be affected in ribosomopathies. Despite the need for ribosomes in all cell types, these diseases result mainly in tissue-specific impairments. Depending on the type of ribosomopathy and its pathogenicity, there are many potential therapeutic targets. The present manuscript will review our knowledge of ribosomopathies, discuss current treatments, and introduce the new therapeutic perspectives based on recent research. Diamond–Blackfan anemia, currently treated with blood transfusion prior to steroids, could be managed with a range of new compounds, acting mainly on anemia, such as L-leucine. Treacher Collins syndrome could be managed by various treatments, but it has recently been shown that proteasomal inhibition by MG132 or Bortezomib may improve cranial skeleton malformations. Developmental defects resulting from ribosomopathies could be also treated pharmacologically after birth. It might thus be possible to treat certain ribosomopathies without using multiple treatments such as surgery and transplants. Ribosomopathies remain an open field in the search for new therapeutic approaches based on our recent understanding of the role of ribosomes and progress in gene therapy for curing genetic disorders.
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14
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Nguyen Thanh L, Nguyen HP, Ngo MD, Bui VA, Dam PTM, Bui HTP, Ngo DV, Tran KT, Dang TTT, Duong BD, Nguyen PAT, Forsyth N, Heke M. Outcomes of bone marrow mononuclear cell transplantation combined with interventional education for autism spectrum disorder. Stem Cells Transl Med 2020; 10:14-26. [PMID: 32902182 PMCID: PMC7780798 DOI: 10.1002/sctm.20-0102] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 07/17/2020] [Accepted: 07/28/2020] [Indexed: 12/24/2022] Open
Abstract
The aim of this study was to evaluate the safety and efficacy of autologous bone marrow mononuclear cell transplantation combined with educational intervention for children with autism spectrum disorder. An open‐label clinical trial was performed from July 2017 to August 2019 at Vinmec International Hospital, Hanoi, Vietnam. Thirty children who fulfilled the autism criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and had Childhood Autism Rating Scale (CARS) scores >37 were selected. Bone marrow was harvested by anterior iliac crest puncture under general anesthesia. The volume collected was as follows: 8 mL/kg for patients under 10 kg (80 mL + [body weight in kg − 10] × 7 mL) for patients above 10 kg. Mononuclear cells were isolated with a Ficoll gradient and then infused intrathecally. The same procedure was repeated 6 months later. After the first transplantation, all patients underwent 8 weeks of educational intervention based on the Early Start Denver Model. There were no severe adverse events associated with transplantation. The severity of autism spectrum disorder (ASD) was significantly reduced, with the median CARS score decreasing from 50 (range 40‐55.5) to 46.5 (range 33.5‐53.5) (P < .05). Adaptive capacity increased, with the median Vineland Adaptive Behavior Scales score rising from 53.5 to 60.5. Social communication, language, and daily skills improved markedly within 18 months after transplantation. Conversely, repetitive behaviors and hyperactivity decreased remarkably. Autologous bone marrow mononuclear cell transplantation in combination with behavioral intervention was safe and well tolerated in children with ASD (Trial registration: ClinicalTrials.gov identifier: NCT03225651).
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Affiliation(s)
- Liem Nguyen Thanh
- Vinmec Research Institute of Stem Cell and Gene Technology (VRISG), Hanoi, Vietnam
| | - Hoang-Phuong Nguyen
- Vinmec Research Institute of Stem Cell and Gene Technology (VRISG), Hanoi, Vietnam
| | - Minh Duy Ngo
- Vinmec Times City International Hospital, Hanoi, Vietnam
| | - Viet Anh Bui
- Vinmec Hightech Center, Vinmec Health Care System, Hanoi, Vietnam
| | - Phuong T M Dam
- Vinmec Hightech Center, Vinmec Health Care System, Hanoi, Vietnam
| | | | - Doan Van Ngo
- Vinmec Times City International Hospital, Hanoi, Vietnam
| | - Kien Trung Tran
- Vinmec Research Institute of Stem Cell and Gene Technology (VRISG), Hanoi, Vietnam
| | | | - Binh Duc Duong
- Vinmec Times City International Hospital, Hanoi, Vietnam
| | | | - Nicholas Forsyth
- Faculty of Medicine & Health Sciences, Keele University, Newcastle, UK
| | - Michael Heke
- Department of Biology, Stanford University, Stanford, California, USA
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15
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Donkervoort S, Mohassel P, Laugwitz L, Zaki MS, Kamsteeg EJ, Maroofian R, Chao KR, Verschuuren-Bemelmans CC, Horber V, Fock AJM, McCarty RM, Jain MS, Biancavilla V, McMacken G, Nalls M, Voermans NC, Elbendary HM, Snyder M, Cai C, Lehky TJ, Stanley V, Iannaccone ST, Foley AR, Lochmüller H, Gleeson J, Houlden H, Haack TB, Horvath R, Bönnemann CG. Biallelic loss of function variants in SYT2 cause a treatable congenital onset presynaptic myasthenic syndrome. Am J Med Genet A 2020; 182:2272-2283. [PMID: 32776697 DOI: 10.1002/ajmg.a.61765] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 05/25/2020] [Accepted: 06/13/2020] [Indexed: 12/15/2022]
Abstract
Synaptotagmins are integral synaptic vesicle membrane proteins that function as calcium sensors and regulate neurotransmitter release at the presynaptic nerve terminal. Synaptotagmin-2 (SYT2), is the major isoform expressed at the neuromuscular junction. Recently, dominant missense variants in SYT2 have been reported as a rare cause of distal motor neuropathy and myasthenic syndrome, manifesting with stable or slowly progressive distal weakness of variable severity along with presynaptic NMJ impairment. These variants are thought to have a dominant-negative effect on synaptic vesicle exocytosis, although the precise pathomechanism remains to be elucidated. Here we report seven patients of five families, with biallelic loss of function variants in SYT2, clinically manifesting with a remarkably consistent phenotype of severe congenital onset hypotonia and weakness, with variable degrees of respiratory involvement. Electrodiagnostic findings were consistent with a presynaptic congenital myasthenic syndrome (CMS) in some. Treatment with an acetylcholinesterase inhibitor pursued in three patients showed clinical improvement with increased strength and function. This series further establishes SYT2 as a CMS-disease gene and expands its clinical and genetic spectrum to include recessive loss-of-function variants, manifesting as a severe congenital onset presynaptic CMS with potential treatment implications.
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Affiliation(s)
- Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Payam Mohassel
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Lucia Laugwitz
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany.,Department of Paediatric Neurology, University Children's Hospital, Tübingen, Germany
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Reza Maroofian
- Department of Neuromuscular Disorders, University College London Institute of Neurology, London, UK
| | - Katherine R Chao
- Center for Mendelian Genomics, Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - Veronka Horber
- Department of Paediatric Neurology, University Children's Hospital, Tübingen, Germany
| | - Annemarie J M Fock
- Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Riley M McCarty
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Minal S Jain
- Rehabilitation Medicine Department, Clinical Research Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Victoria Biancavilla
- Rehabilitation Medicine Department, Clinical Research Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Grace McMacken
- Department of Neurosciences, Royal Victoria Hospital, Belfast, UK
| | - Matthew Nalls
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Nicol C Voermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Hasnaa M Elbendary
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Molly Snyder
- Department of Neurology, Children's Health, Dallas, Texas, USA
| | - Chunyu Cai
- Department of Pathology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Tanya J Lehky
- EMG Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Valentina Stanley
- Laboratory for Pediatric Brain Disease, Howard Hughes Medical Institute, University of California, San Diego, California, USA.,Rady Children's Institute for Genomic Medicine, Rady Children's Hospital, San Diego, California, USA
| | - Susan T Iannaccone
- Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA
| | - A Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Hanns Lochmüller
- Department of Neuropediatrics and Muscle Disorders, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany.,Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada.,Division of Neurology, Department of Medicine, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Joseph Gleeson
- Laboratory for Pediatric Brain Disease, Howard Hughes Medical Institute, University of California, San Diego, California, USA.,Rady Children's Institute for Genomic Medicine, Rady Children's Hospital, San Diego, California, USA
| | - Henry Houlden
- Department of Neuromuscular Disorders, University College London Institute of Neurology, London, UK
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
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16
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Pillon MC, Goslen KH, Gordon J, Wells ML, Williams JG, Stanley RE. It takes two (Las1 HEPN endoribonuclease domains) to cut RNA correctly. J Biol Chem 2020; 295:5857-5870. [PMID: 32220933 DOI: 10.1074/jbc.ra119.011193] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 03/23/2020] [Indexed: 12/26/2022] Open
Abstract
The ribosome biogenesis factor Las1 is an essential endoribonuclease that is well-conserved across eukaryotes and a newly established member of the higher eukaryotes and prokaryotes nucleotide-binding (HEPN) domain-containing nuclease family. HEPN nucleases participate in diverse RNA cleavage pathways and share a short HEPN nuclease motif (RφXXXH) important for RNA cleavage. Most HEPN nucleases participate in stress-activated RNA cleavage pathways; Las1 plays a fundamental role in processing pre-rRNA. Underscoring the significance of Las1 function in the cell, mutations in the human LAS1L (LAS1-like) gene have been associated with neurological dysfunction. Two juxtaposed HEPN nuclease motifs create Las1's composite nuclease active site, but the roles of the individual HEPN motif residues are poorly defined. Here using a combination of in vivo experiments in Saccharomyces cerevisiae and in vitro assays, we show that both HEPN nuclease motifs are required for Las1 nuclease activity and fidelity. Through in-depth sequence analysis and systematic mutagenesis, we determined the consensus HEPN motif in the Las1 subfamily and uncovered its canonical and specialized elements. Using reconstituted Las1 HEPN-HEPN' chimeras, we defined the molecular requirements for RNA cleavage. Intriguingly, both copies of the Las1 HEPN motif were important for nuclease function, revealing that both HEPN motifs participate in coordinating the RNA within the Las1 active site. We also established that conformational flexibility of the two HEPN domains is important for proper nuclease function. The results of our work reveal critical information about how dual HEPN domains come together to drive Las1-mediated RNA cleavage.
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Affiliation(s)
- Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - Kevin H Goslen
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - Jacob Gordon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - Melissa L Wells
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - Jason G Williams
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709.
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17
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Tran KT, Le VS, Bui HTP, Do DH, Ly HTT, Nguyen HT, Dao LTM, Nguyen TH, Vu DM, Ha LT, Le HTT, Mukhopadhyay A, Nguyen LT. Genetic landscape of autism spectrum disorder in Vietnamese children. Sci Rep 2020; 10:5034. [PMID: 32193494 PMCID: PMC7081304 DOI: 10.1038/s41598-020-61695-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 02/18/2020] [Indexed: 12/19/2022] Open
Abstract
Autism spectrum disorder (ASD) is a complex disorder with an unclear aetiology and an estimated global prevalence of 1%. However, studies of ASD in the Vietnamese population are limited. Here, we first conducted whole exome sequencing (WES) of 100 children with ASD and their unaffected parents. Our stringent analysis pipeline was able to detect 18 unique variants (8 de novo and 10 ×-linked, all validated), including 12 newly discovered variants. Interestingly, a notable number of X-linked variants were detected (56%), and all of them were found in affected males but not in affected females. We uncovered 17 genes from our ASD cohort in which CHD8, DYRK1A, GRIN2B, SCN2A, OFD1 and MDB5 have been previously identified as ASD risk genes, suggesting the universal aetiology of ASD for these genes. In addition, we identified six genes that have not been previously reported in any autism database: CHM, ENPP1, IGF1, LAS1L, SYP and TBX22. Gene ontology and phenotype-genotype analysis suggested that variants in IGF1, SYP and LAS1L could plausibly confer risk for ASD. Taken together, this study adds to the genetic heterogeneity of ASD and is the first report elucidating the genetic landscape of ASD in Vietnamese children.
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Affiliation(s)
- Kien Trung Tran
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam
| | - Vinh Sy Le
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam.
- University of Engineering and Technology, Vietnam National University Hanoi, 144 Xuan Thuy, Cau Giay ditrict, Hanoi, Vietnam.
| | - Hoa Thi Phuong Bui
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Duong Huy Do
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Ha Thi Thanh Ly
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Hieu Thi Nguyen
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam
| | - Lan Thi Mai Dao
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam
| | - Thanh Hong Nguyen
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam
| | - Duc Minh Vu
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Lien Thi Ha
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Huong Thi Thanh Le
- Department of Gene Technology, Hi-tech Center, Vinmec International Hospital, 458 Minh Khai, Hai Ba Trung district, Hanoi, Hanoi, Vietnam
| | - Arijit Mukhopadhyay
- Translational Medicine Laboratory, Biomedical Research Centre, School of Science, Engineering and Environment, University of Salford, Manchester, M5 4WT, United Kingdom
| | - Liem Thanh Nguyen
- Vinmec Research Institute of Stem Cell and Gene Technology, 458 Minh Khai, Hai Ba Trung district, Hanoi, Vietnam.
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18
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Thelen MP, Kye MJ. The Role of RNA Binding Proteins for Local mRNA Translation: Implications in Neurological Disorders. Front Mol Biosci 2020; 6:161. [PMID: 32010708 PMCID: PMC6974540 DOI: 10.3389/fmolb.2019.00161] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/20/2019] [Indexed: 12/11/2022] Open
Abstract
As neurons are one of the most highly polarized cells in our body, they require sophisticated cellular mechanisms to maintain protein homeostasis in their subcellular compartments such as axons and dendrites. When neuronal protein homeostasis is disturbed due to genetic mutations or deletions, this often results in degeneration of neurons leading to devastating outcome such as spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), and fragile X syndrome (FXS). Ribonucleoprotein (RNP) complexes are macromolecular complexes composed of RNA binding proteins (RBPs) and their target RNAs. RBPs contain RNA binding domains and bind to RNA molecules via specific sequence motifs. RNP complexes have various functions in gene expression including messenger RNA (mRNA) trafficking, RNA processing and silencing. In neurons, RBPs deliver specific sets of mRNAs to subcellular compartments such as axons and dendrites to be locally translated. Mutations or deletions in genes coding for RNPs have been reported as causes for neurological disorders such as SMA, ALS, and FXS. As RBPs determine axonal or dendritic mRNA repertoires as well as proteomes by trafficking selective mRNAs and regulating local protein synthesis, they play a crucial role for neuronal function. In this review, we summarize the role of well-known RBPs, SMN, TDP-43, FUS, and FMRP, and review their function for local protein synthesis in neurons. Furthermore, we discuss their pathological contribution to the neurological disorders.
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Affiliation(s)
| | - Min Jeong Kye
- Institute of Human Genetics, University of Cologne, Cologne, Germany
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19
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Pillon MC, Lo YH, Stanley RE. IT'S 2 for the price of 1: Multifaceted ITS2 processing machines in RNA and DNA maintenance. DNA Repair (Amst) 2019; 81:102653. [PMID: 31324529 PMCID: PMC6764878 DOI: 10.1016/j.dnarep.2019.102653] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cells utilize sophisticated RNA processing machines to ensure the quality of RNA. Many RNA processing machines have been further implicated in regulating the DNA damage response signifying a strong link between RNA processing and genome maintenance. One of the most intricate and highly regulated RNA processing pathways is the processing of the precursor ribosomal RNA (pre-rRNA), which is paramount for the production of ribosomes. Removal of the Internal Transcribed Spacer 2 (ITS2), located between the 5.8S and 25S rRNA, is one of the most complex steps of ribosome assembly. Processing of the ITS2 is initiated by the newly discovered endoribonuclease Las1, which cleaves at the C2 site within the ITS2, generating products that are further processed by the polynucleotide kinase Grc3, the 5'→3' exonuclease Rat1, and the 3'→5' RNA exosome complex. In addition to their defined roles in ITS2 processing, these critical cellular machines participate in other stages of ribosome assembly, turnover of numerous cellular RNAs, and genome maintenance. Here we summarize recent work defining the molecular mechanisms of ITS2 processing by these essential RNA processing machines and highlight their emerging roles in transcription termination, heterochromatin function, telomere maintenance, and DNA repair.
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Affiliation(s)
- Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Yu-Hua Lo
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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20
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Pillon MC, Hsu AL, Krahn JM, Williams JG, Goslen KH, Sobhany M, Borgnia MJ, Stanley RE. Cryo-EM reveals active site coordination within a multienzyme pre-rRNA processing complex. Nat Struct Mol Biol 2019; 26:830-839. [PMID: 31488907 PMCID: PMC6733591 DOI: 10.1038/s41594-019-0289-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 07/30/2019] [Indexed: 12/22/2022]
Abstract
Ribosome assembly is a complex process reliant on the coordination of trans-acting enzymes to produce functional ribosomal subunits and secure the translational capacity of cells. The endoribonuclease (RNase) Las1 and the polynucleotide kinase (PNK) Grc3 assemble into a multienzyme complex, herein designated RNase PNK, to orchestrate processing of precursor ribosomal RNA (rRNA). RNase PNK belongs to the functionally diverse HEPN nuclease superfamily, whose members rely on distinct cues for nuclease activation. To establish how RNase PNK coordinates its dual enzymatic activities, we solved a series of cryo-EM structures of Chaetomium thermophilum RNase PNK in multiple conformational states. The structures reveal that RNase PNK adopts a butterfly-like architecture, harboring a composite HEPN nuclease active site flanked by discrete RNA kinase sites. We identify two molecular switches that coordinate nuclease and kinase function. Together, our structures and corresponding functional studies establish a new mechanism of HEPN nuclease activation essential for ribosome production.
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Affiliation(s)
- Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Allen L Hsu
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Juno M Krahn
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Jason G Williams
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Kevin H Goslen
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Mack Sobhany
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Mario J Borgnia
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, Durham, NC, USA.
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21
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Gordon J, Pillon MC, Stanley RE. Nol9 Is a Spatial Regulator for the Human ITS2 Pre-rRNA Endonuclease-Kinase Complex. J Mol Biol 2019; 431:3771-3786. [PMID: 31288032 DOI: 10.1016/j.jmb.2019.07.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/28/2019] [Accepted: 07/01/2019] [Indexed: 12/01/2022]
Abstract
The ribosome plays a universal role in translating the cellular proteome. Defects in the ribosome assembly factor Las1L are associated with congenital lethal motor neuron disease and X-linked intellectual disability disorders, yet its role in processing precursor ribosomal RNA (pre-rRNA) is largely unclear. The Las1L endoribonuclease associates with the Nol9 polynucleotide kinase to form the internal transcribed spacer 2 (ITS2) pre-rRNA endonuclease-kinase machinery. Together, Las1L-Nol9 catalyzes RNA cleavage and phosphorylation to mark the ITS2 for degradation. While ITS2 processing is critical for the production of functional ribosomes, the regulation of mammalian Las1L-Nol9 remains obscure. Here we characterize the human Las1L-Nol9 complex and identify critical molecular features that regulate its assembly and spatial organization. We establish that Las1L and Nol9 form a higher-order complex and identify the regions responsible for orchestrating this intricate architecture. Structural analysis by high-resolution imaging defines the intricate spatial pattern of Las1L-Nol9 within the nucleolar sub-structure linked with late pre-rRNA processing events. Furthermore, we uncover a Nol9-encoded nucleolar localization sequence that is responsible for nucleolar transport of the assembled Las1L-Nol9 complex. Together, these data provide a mechanism for the assembly and nucleolar localization of the human ITS2 pre-rRNA endonuclease-kinase complex.
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Affiliation(s)
- Jacob Gordon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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22
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Zanni G, Nardella M, Barresi S, Bellacchio E, Niceta M, Ciolfi A, Pro S, D'Arrigo S, Tartaglia M, Bertini E. De novo p.T362R mutation in MORC2 causes early onset cerebellar ataxia, axonal polyneuropathy and nocturnal hypoventilation. Brain 2019; 140:e34. [PMID: 28402445 DOI: 10.1093/brain/awx083] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Ginevra Zanni
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marta Nardella
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sabina Barresi
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Andrea Ciolfi
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Stefano Pro
- Department of Neurosciences, Unit of Neurology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Stefano D'Arrigo
- Developmental Neurology Division, IRCCS Fondazione Istituto Neurologico C. Besta, Milan, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Enrico Bertini
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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23
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Hetman M, Slomnicki LP. Ribosomal biogenesis as an emerging target of neurodevelopmental pathologies. J Neurochem 2018; 148:325-347. [PMID: 30144322 DOI: 10.1111/jnc.14576] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/15/2018] [Accepted: 08/21/2018] [Indexed: 12/17/2022]
Abstract
Development of the nervous system is carried out by complex gene expression programs that are regulated at both transcriptional and translational level. In addition, quality control mechanisms such as the TP53-mediated apoptosis or neuronal activity-stimulated survival ensure successful neurogenesis and formation of functional circuitries. In the nucleolus, production of ribosomes is essential for protein synthesis. In addition, it participates in chromatin organization and regulates the TP53 pathway via the ribosomal stress response. Its tight regulation is required for maintenance of genomic integrity. Mutations in several ribosomal components and trans-acting ribosomal biogenesis factors result in neurodevelopmental syndromes that present with microcephaly, autism, intellectual deficits and/or progressive neurodegeneration. Furthermore, ribosomal biogenesis is perturbed by exogenous factors that disrupt neurodevelopment including alcohol or Zika virus. In this review, we present recent literature that argues for a role of dysregulated ribosomal biogenesis in pathogenesis of various neurodevelopmental syndromes. We also discuss potential mechanisms through which such dysregulation may lead to cellular pathologies of the developing nervous system including insufficient proliferation and/or loss of neuroprogenitors cells, apoptosis of immature neurons, altered neuronal morphogenesis, and neurodegeneration.
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Affiliation(s)
- Michal Hetman
- Departments of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, Louisville, Kentucky, USA.,Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
| | - Lukasz P Slomnicki
- Departments of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, Louisville, Kentucky, USA
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24
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Lambert CJ, Freshner BC, Chung A, Stevenson TJ, Bowles DM, Samuel R, Gale BK, Bonkowsky JL. An automated system for rapid cellular extraction from live zebrafish embryos and larvae: Development and application to genotyping. PLoS One 2018; 13:e0193180. [PMID: 29543903 PMCID: PMC5854293 DOI: 10.1371/journal.pone.0193180] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 02/06/2018] [Indexed: 01/31/2023] Open
Abstract
Zebrafish are a valuable model organism in biomedical research. Their rapid development, ability to model human diseases, utility for testing genetic variants identified from next-generation sequencing, amenity to CRISPR mutagenesis, and potential for therapeutic compound screening, has led to their wide-spread adoption in diverse fields of study. However, their power for large-scale screens is limited by the absence of automated genotyping tools for live animals. This constrains potential drug screen options, limits analysis of embryonic and larval phenotypes, and requires raising additional animals to adulthood to ensure obtaining an animal of the desired genotype. Our objective was to develop an automated system that would rapidly obtain cells and DNA from zebrafish embryos and larvae for genotyping, and that would keep the animals alive. We describe the development, testing, and validation of a zebrafish embryonic genotyping device, termed “ZEG” (Zebrafish Embryo Genotyper). Using microfluidic harmonic oscillation of the animal on a roughened glass surface, the ZEG is able to obtain genetic material (cells and DNA) for use in genotyping, from 24 embryos or larvae simultaneously in less than 10 minutes. Loading and unloading of the ZEG is performed manually with a standard pipette tip or transfer pipette. The obtained genetic material is amplified by PCR and can be used for subsequent analysis including sequencing, gel electrophoresis, or high-resolution melt-analysis. Sensitivity of genotyping and survival of animals are both greater than 90%. There are no apparent effects on body morphology, development, or motor behavior tests. In summary, the ZEG device enables rapid genotyping of live zebrafish embryos and larvae, and animals are available for downstream applications, testing, or raising.
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Affiliation(s)
- Christopher J Lambert
- Department of Mechanical Engineering, University of Utah, Salt Lake City, Utah, United States of America
| | - Briana C Freshner
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Arlen Chung
- Department of Mechanical Engineering, University of Utah, Salt Lake City, Utah, United States of America
| | - Tamara J Stevenson
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - D Miranda Bowles
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Raheel Samuel
- Department of Mechanical Engineering, University of Utah, Salt Lake City, Utah, United States of America.,Nanonc Inc., Salt Lake City, Utah, United States of America
| | - Bruce K Gale
- Department of Mechanical Engineering, University of Utah, Salt Lake City, Utah, United States of America.,Nanonc Inc., Salt Lake City, Utah, United States of America
| | - Joshua L Bonkowsky
- Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
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25
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Habibi Zoham M, Eghbalkhah A, Kamrani K, Khosroshahi N, Yousefimanesh H, Eskandarizadeh Z. Distal Spinal Muscular Atrophy: An Overlooked Etiology of Weaning Failure in Children with Respiratory Insufficiency. J Pediatr Intensive Care 2018; 7:159-162. [PMID: 31073488 DOI: 10.1055/s-0037-1617434] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 12/01/2017] [Indexed: 10/18/2022] Open
Abstract
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disorder that involves the anterior horn motor neurons. It is a disease with a poor prognosis presenting with progressive distal motor weakness and respiratory insufficiency from diaphragmatic paralysis followed by distal muscle weakness before 6 months of age. With the intent to spread the awareness of this rare and life-threatening disease, we report a 2.5-month-old female infant with a subsequent diagnosis of SMARD1, who was admitted in our pediatric intensive care unit with chief complaint of progressive respiratory distress and poor feeding.
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Affiliation(s)
- Mojdeh Habibi Zoham
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Asgar Eghbalkhah
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Kamyar Kamrani
- Department of Neonatal Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Nahid Khosroshahi
- Department of Pediatric Neurology, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Hossein Yousefimanesh
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
| | - Zahra Eskandarizadeh
- Department of Pediatric Intensive Care Unit, Bahrami Children's Hospital, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran
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26
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Preribosomes escaping from the nucleus are caught during translation by cytoplasmic quality control. Nat Struct Mol Biol 2017; 24:1107-1115. [PMID: 29083413 DOI: 10.1038/nsmb.3495] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/04/2017] [Indexed: 12/28/2022]
Abstract
Assembly of fully functional ribosomes is a prerequisite for failsafe translation. This explains why maturing preribosomal subunits have to pass through an array of quality-control checkpoints, including nuclear export, to ensure that only properly assembled ribosomes engage in translation. Despite these safeguards, we found that nuclear pre-60S particles unable to remove a transient structure composed of ITS2 pre-rRNA and associated assembly factors, termed the 'foot', escape to the cytoplasm, where they can join with mature 40S subunits to catalyze protein synthesis. However, cells harboring these abnormal ribosomes show translation defects indicated by the formation of 80S ribosomes poised with pre-60S subunits carrying tRNAs in trapped hybrid states. To overcome this translational stress, the cytoplasmic surveillance machineries RQC and Ski-exosome target these malfunctioning ribosomes. Thus, pre-60S subunits that escape nuclear quality control can enter translation, but are caught by cytoplasmic surveillance mechanisms.
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27
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Pillon MC, Stanley RE. Nuclease integrated kinase super assemblies (NiKs) and their role in RNA processing. Curr Genet 2017; 64:183-190. [PMID: 28929238 DOI: 10.1007/s00294-017-0749-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/08/2017] [Accepted: 09/11/2017] [Indexed: 01/24/2023]
Abstract
Here we highlight the Grc3/Las1 complex, an essential RNA processing machine that is well conserved across eukaryotes and required for processing the pre-ribosomal RNA (pre-rRNA). Las1 is an endoribonuclease that cleaves the pre-rRNA while Grc3 is a polynucleotide kinase that phosphorylates the Las1-cleaved RNA product. Recently we showed that Grc3 and Las1 assemble into a higher-order complex composed of a dimer of Grc3/Las1 heterodimers that is required for nuclease and kinase activity. Unexpectedly, we found that the Grc3/Las1 complex draws numerous parallels with two other eukaryotic nucleases, Ire1 and RNase L. In this perspective we explore the similarities and differences between this family of nuclease integrated kinase super assemblies (NiKs) and their distinct roles in RNA cleavage.
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Affiliation(s)
- Monica C Pillon
- Signal Transduction Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Robin E Stanley
- Signal Transduction Laboratory, Department of Health and Human Services, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC, 27709, USA.
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28
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Xie Q, Li C, Song X, Wu L, Jiang Q, Qiu Z, Cao H, Yu K, Wan C, Li J, Yang F, Huang Z, Niu B, Jiang Z, Zhang T. Folate deficiency facilitates recruitment of upstream binding factor to hot spots of DNA double-strand breaks of rRNA genes and promotes its transcription. Nucleic Acids Res 2017; 45:2472-2489. [PMID: 27924000 PMCID: PMC5389733 DOI: 10.1093/nar/gkw1208] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 11/22/2016] [Indexed: 12/24/2022] Open
Abstract
The biogenesis of ribosomes in vivo is an essential process for cellular functions. Transcription of ribosomal RNA (rRNA) genes is the rate-limiting step in ribosome biogenesis controlled by environmental conditions. Here, we investigated the role of folate antagonist on changes of DNA double-strand breaks (DSBs) landscape in mouse embryonic stem cells. A significant DSB enhancement was detected in the genome of these cells and a large majority of these DSBs were found in rRNA genes. Furthermore, spontaneous DSBs in cells under folate deficiency conditions were located exclusively within the rRNA gene units, representing a H3K4me1 hallmark. Enrichment H3K4me1 at the hot spots of DSB regions enhanced the recruitment of upstream binding factor (UBF) to rRNA genes, resulting in the increment of rRNA genes transcription. Supplement of folate resulted in a restored UBF binding across DNA breakage sites of rRNA genes, and normal rRNA gene transcription. In samples from neural tube defects (NTDs) with low folate level, up-regulation of rRNA gene transcription was observed, along with aberrant UBF level. Our results present a new view by which alterations in folate levels affects DNA breakage through epigenetic control leading to the regulation of rRNA gene transcription during the early stage of development.
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Affiliation(s)
- Qiu Xie
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Caihua Li
- Genesky Biotechnologies Inc, Shanghai 200120, China
| | - Xiaozhen Song
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Lihua Wu
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Qian Jiang
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Zhiyong Qiu
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Haiyan Cao
- Department of Laboratory Medicine, The Fourth Affiliated Hospital of Harbin Medical University, Harbin 150081, China
| | - Kaihui Yu
- Department of Pathophysiology, Guangxi Medical University, Guangxi 530021, China
| | - Chunlei Wan
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | - Jianting Li
- Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan 030001, China
| | - Feng Yang
- Genesky Biotechnologies Inc, Shanghai 200120, China
| | - Zebing Huang
- Genesky Biotechnologies Inc, Shanghai 200120, China
| | - Bo Niu
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
| | | | - Ting Zhang
- Beijing Municipal Key Laboratory of Child Development and Nutriomics, Capital Institute of Pediatrics-Peking University Teaching Hospital, Beijing 100020, China
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29
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Grc3 programs the essential endoribonuclease Las1 for specific RNA cleavage. Proc Natl Acad Sci U S A 2017; 114:E5530-E5538. [PMID: 28652339 DOI: 10.1073/pnas.1703133114] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Las1 is a recently discovered endoribonuclease that collaborates with Grc3-Rat1-Rai1 to process precursor ribosomal RNA (rRNA), yet its mechanism of action remains unknown. Disruption of the mammalian Las1 gene has been linked to congenital lethal motor neuron disease and X-linked intellectual disability disorders, thus highlighting the necessity to understand Las1 regulation and function. Here, we report that the essential Las1 endoribonuclease requires its binding partner, the polynucleotide kinase Grc3, for specific C2 cleavage. Our results establish that Grc3 drives Las1 endoribonuclease cleavage to its targeted C2 site both in vitro and in Saccharomyces cerevisiae. Moreover, we observed Las1-dependent activation of the Grc3 kinase activity exclusively toward single-stranded RNA. Together, Las1 and Grc3 assemble into a tetrameric complex that is required for competent rRNA processing. The tetrameric Grc3/Las1 cross talk draws unexpected parallels to endoribonucleases RNaseL and Ire1, and establishes Grc3/Las1 as a unique member of the RNaseL/Ire1 RNA splicing family. Together, our work provides mechanistic insight for the regulation of the Las1 endoribonuclease and identifies the tetrameric Grc3/Las1 complex as a unique example of a protein-guided programmable endoribonuclease.
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30
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Powis Z, Hart A, Cherny S, Petrik I, Palmaer E, Tang S, Jones C. Clinical diagnostic exome evaluation for an infant with a lethal disorder: genetic diagnosis of TARP syndrome and expansion of the phenotype in a patient with a newly reported RBM10 alteration. BMC MEDICAL GENETICS 2017; 18:60. [PMID: 28577551 PMCID: PMC5455125 DOI: 10.1186/s12881-017-0426-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 05/22/2017] [Indexed: 11/11/2022]
Abstract
Background Diagnostic Exome Sequencing (DES) has been shown to be an effective tool for diagnosis individuals with suspected genetic conditions. Case Presentation We report a male infant born with multiple anomalies including bilateral dysplastic kidneys, cleft palate, bilateral talipes, and bilateral absence of thumbs and first toes. Prenatal testing including chromosome analysis and microarray did not identify a cause for the multiple congenital anomalies. Postnatal diagnostic exome studies (DES) were utilized to find a molecular diagnosis for the patient. Exome sequencing of the proband, mother, and father showed a previously unreported maternally inherited RNA binding motif protein 10 (RBM10) c.1352_1353delAG (p.E451Vfs*66) alteration. Mutations in RBM10 are associated with TARP syndrome, an X-linked recessive disorder originally described with cardinal features of talipes equinovarus, atrial septal defect, Robin sequence, and persistent left superior vena cava. Conclusion DES established a molecular genetic diagnosis of TARP syndrome for a neonatal patient with a poor prognosis in whom traditional testing methods were uninformative and allowed for efficient diagnosis and future reproductive options for the parents. Other reported cases of TARP syndrome demonstrate significant variability in clinical phenotype. The reported features in this infant including multiple hemivertebrae, imperforate anus, aplasia of thumbs and first toes have not been reported in previous patients, thus expanding the clinical phenotype for this rare disorder. Electronic supplementary material The online version of this article (doi:10.1186/s12881-017-0426-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zöe Powis
- Ambry Genetics, 15 Argonaut, Aliso Viejo, CA, 92656, USA.
| | - Alexa Hart
- Rush University Medical Center, Chicago, IL, USA
| | - Sara Cherny
- Rush University Medical Center, Chicago, IL, USA
| | - Igor Petrik
- Ambry Genetics, 15 Argonaut, Aliso Viejo, CA, 92656, USA
| | - Erika Palmaer
- Ambry Genetics, 15 Argonaut, Aliso Viejo, CA, 92656, USA
| | - Sha Tang
- Ambry Genetics, 15 Argonaut, Aliso Viejo, CA, 92656, USA
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31
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Abstract
Paediatric motor neuron diseases encompass a group of neurodegenerative diseases characterised by the onset of muscle weakness and atrophy before the age of 18 years, attributable to motor neuron loss across various neuronal networks in the brain and spinal cord. While the genetic underpinnings are diverse, advances in next generation sequencing have transformed diagnostic paradigms. This has reinforced the clinical phenotyping and molecular genetic expertise required to navigate the complexities of such diagnoses. In turn, improved genetic technology and subsequent gene identification have enabled further insights into the mechanisms of motor neuron degeneration and how these diseases form part of a neurodegenerative disorder spectrum. Common pathophysiologies include abnormalities in axonal architecture and function, RNA processing, and protein quality control. This review incorporates an overview of the clinical manifestations, genetics, and pathophysiology of inherited paediatric motor neuron disorders beyond classic SMN1-related spinal muscular atrophy and describes recent advances in next generation sequencing and its clinical application. Specific disease-modifying treatment is becoming a clinical reality in some disorders of the motor neuron highlighting the importance of a timely and specific diagnosis.
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32
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Yuan JH, Hashiguchi A, Yoshimura A, Yaguchi H, Tsuzaki K, Ikeda A, Wada-Isoe K, Ando M, Nakamura T, Higuchi Y, Hiramatsu Y, Okamoto Y, Takashima H. Clinical diversity caused by novel IGHMBP2 variants. J Hum Genet 2017; 62:599-604. [PMID: 28202949 DOI: 10.1038/jhg.2017.15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/08/2017] [Accepted: 01/12/2017] [Indexed: 11/09/2022]
Abstract
Immunoglobulin helicase μ-binding protein 2 (IGHMBP2) gene is responsible for Charcot-Marie-Tooth disease (CMT) type 2S and spinal muscular atrophy with respiratory distress type 1 (SMARD1). From June 2014 to December 2015, we collected 408 cases, who referred to our genetic laboratory for genetic analysis, suspected with CMT disease or other inherited peripheral neuropathies (IPNs) on the basis of clinical manifestations and electrophysiological studies. Mutation screening was performed using Ion AmpliSeq Custom Panels, which comprise 72 disease-causing or candidate genes of IPNs. We identified novel homozygous or compound heterozygous variants of IGHMBP2 in four patients. Three patients presented with childhood-onset axonal predominant sensorimotor polyneuropathies, whereas the other case was diagnosed with SMARD1, manifesting as low birth weight, weak cry, reduced spontaneous movement and developed respiratory distress 4 months after birth. We present the original report of CMT type 2S in Japan, and illustrate that recessive IGHMBP2 variants account for ~1.6% of axonal CMT in our cohort.
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Affiliation(s)
- Jun-Hui Yuan
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Akihiro Hashiguchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Hiroshi Yaguchi
- Department of Neurology, The Jikei University Kashiwa Hospital, Chiba, Japan
| | - Koji Tsuzaki
- Department of Neurology, Kansai Electric Power Hospital, Osaka, Japan
| | - Azusa Ikeda
- Kanagawa Children's Medical Center, Yokohama, Japan
| | - Kenji Wada-Isoe
- Division of Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Tomonori Nakamura
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yujiro Higuchi
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yu Hiramatsu
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima City, Japan
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33
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Farwell Hagman KD, Shinde DN, Mroske C, Smith E, Radtke K, Shahmirzadi L, El-Khechen D, Powis Z, Chao EC, Alcaraz WA, Helbig KL, Sajan SA, Rossi M, Lu HM, Huether R, Li S, Wu S, Nuñes ME, Tang S. Candidate-gene criteria for clinical reporting: diagnostic exome sequencing identifies altered candidate genes among 8% of patients with undiagnosed diseases. Genet Med 2016; 19:224-235. [PMID: 27513193 PMCID: PMC5303763 DOI: 10.1038/gim.2016.95] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/25/2016] [Indexed: 02/07/2023] Open
Abstract
Purpose: Diagnostic exome sequencing (DES) is now a commonly ordered test for individuals with undiagnosed genetic disorders. In addition to providing a diagnosis for characterized diseases, exome sequencing has the capacity to uncover novel candidate genes for disease. Methods: Family-based DES included analysis of both characterized and novel genetic etiologies. To evaluate candidate genes for disease in the clinical setting, we developed a systematic, rule-based classification schema. Results: Testing identified a candidate gene among 7.7% (72/934) of patients referred for DES; 37 (4.0%) and 35 (3.7%) of the genes received evidence scores of “candidate” and “suspected candidate,” respectively. A total of 71 independent candidate genes were reported among the 72 patients, and 38% (27/71) were subsequently corroborated in the peer-reviewed literature. This rate of corroboration increased to 51.9% (27/52) among patients whose gene was reported at least 12 months previously. Conclusions: Herein, we provide transparent, comprehensive, and standardized scoring criteria for the clinical reporting of candidate genes. These results demonstrate that DES is an integral tool for genetic diagnosis, especially for elucidating the molecular basis for both characterized and novel candidate genetic etiologies. Gene discoveries also advance the understanding of normal human biology and more common diseases. Genet Med19 2, 224–235.
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Affiliation(s)
| | - Deepali N Shinde
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Cameron Mroske
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Erica Smith
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Kelly Radtke
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Layla Shahmirzadi
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Dima El-Khechen
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Zöe Powis
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Elizabeth C Chao
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA.,Division of Genetics and Genomics, Department of Pediatrics, University of California, Irvine, Irvine, California, USA
| | - Wendy A Alcaraz
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Katherine L Helbig
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Samin A Sajan
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Mari Rossi
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Hsiao-Mei Lu
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Robert Huether
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Shuwei Li
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Sitao Wu
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
| | - Mark E Nuñes
- Department of Genetics, Kaiser Permanente, San Diego, California, USA
| | - Sha Tang
- Department of Clinical Genomics, Ambry Genetics, Aliso Viejo, California, USA
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Gasse L, Flemming D, Hurt E. Coordinated Ribosomal ITS2 RNA Processing by the Las1 Complex Integrating Endonuclease, Polynucleotide Kinase, and Exonuclease Activities. Mol Cell 2016; 60:808-815. [PMID: 26638174 DOI: 10.1016/j.molcel.2015.10.021] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/11/2015] [Accepted: 10/09/2015] [Indexed: 12/28/2022]
Abstract
The rapidly evolving internal transcribed spacer 2 (ITS2) in the pre-ribosomal RNA is one of the most commonly applied phylogenetic markers at species and genus level. Yet, during ribosome biogenesis ITS2 is removed in all eukaryotes by a common, but still unknown, mechanism. Here we describe the existence of an RNA processome, assembled from four conserved subunits, Las1-Grc3-Rat1-Rai1, that carries all the necessary RNA processing enzymes to mediate coordinated ITS2 rRNA removal. Las1 is the long-sought-after endonuclease cleaving 27SB pre-rRNA at site C2 to yield a 5'-OH end at the 26S pre-rRNA and 2',3' cyclic phosphate at the 3' end of 7S pre-rRNA. Subsequently, polynucleotide kinase Grc3 catalyzes ATP-dependent 5'-OH phosphorylation of 26S pre-rRNA, which in turn enables Rat1-Rai1 exonuclease to generate 25S' pre-rRNA. ITS2 processing is reminiscent of tRNA splicing, but instead of subsequent tRNA ligation, the Las1 complex carries along an exonuclease tool to degrade the ITS2 rRNA.
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Affiliation(s)
- Lisa Gasse
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, Heidelberg 69120, Germany
| | - Dirk Flemming
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, Heidelberg 69120, Germany
| | - Ed Hurt
- Biochemie-Zentrum der Universität Heidelberg, Im Neuenheimer Feld 328, Heidelberg 69120, Germany.
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Gund C, Powis Z, Alcaraz W, Desai S, Baranano K. Identification of a syndrome comprising microcephaly and intellectual disability but not white matter disease associated with a homozygous c.676C>T p.R226W DEAF1 mutation. Am J Med Genet A 2016; 170A:1330-2. [PMID: 26834045 DOI: 10.1002/ajmg.a.37580] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 01/21/2016] [Indexed: 11/07/2022]
Abstract
We evaluated a 13-year-old East Pakistani male affected with microcephaly, apparent intellectual disability, hypotonia, and brisk reflexes without spasticity. His parents were first cousins. The patient also had a brother who was similarly affected and died at 10 years due to an accident. Previous SNP array testing showed a 1.63 Mb duplication at 16p13.11 of uncertain significance along with regions of homozygosity. Exome sequencing identified a known pathogenic homozygous alteration in DEAF1, c.676C>T (p.R226W), in this patient. The alteration had been reported in two individuals from a consanguineous Saudi Arabian family. Both individuals had microcephaly, intellectual disability, hypotonia, feeding difficulties, and poor growth. The patient reported here did not have evidence of white matter disease, as had been reported with prior patients. We conclude that this DEAF1 gene alteration caused this patient's symptoms and that white matter disease should not be considered a obligate feature of this syndrome.
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Affiliation(s)
| | - Zöe Powis
- Ambry Genetics, 15 Argonaut, Aliso Viejo, California
| | - Wendy Alcaraz
- Ambry Genetics, 15 Argonaut, Aliso Viejo, California
| | - Sonal Desai
- Kennedy Krieger Institute, Baltimore, Maryland
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36
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Ingram G, Barwick KES, Hartley L, McEntagart M, Crosby AH, Llewelyn G, Morris HR. Distal hereditary motor neuropathy with vocal cord paresis: from difficulty in choral singing to a molecular genetic diagnosis. Pract Neurol 2016; 16:247-51. [DOI: 10.1136/practneurol-2015-001307] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2015] [Indexed: 11/04/2022]
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37
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Hu H, Haas SA, Chelly J, Van Esch H, Raynaud M, de Brouwer APM, Weinert S, Froyen G, Frints SGM, Laumonnier F, Zemojtel T, Love MI, Richard H, Emde AK, Bienek M, Jensen C, Hambrock M, Fischer U, Langnick C, Feldkamp M, Wissink-Lindhout W, Lebrun N, Castelnau L, Rucci J, Montjean R, Dorseuil O, Billuart P, Stuhlmann T, Shaw M, Corbett MA, Gardner A, Willis-Owen S, Tan C, Friend KL, Belet S, van Roozendaal KEP, Jimenez-Pocquet M, Moizard MP, Ronce N, Sun R, O'Keeffe S, Chenna R, van Bömmel A, Göke J, Hackett A, Field M, Christie L, Boyle J, Haan E, Nelson J, Turner G, Baynam G, Gillessen-Kaesbach G, Müller U, Steinberger D, Budny B, Badura-Stronka M, Latos-Bieleńska A, Ousager LB, Wieacker P, Rodríguez Criado G, Bondeson ML, Annerén G, Dufke A, Cohen M, Van Maldergem L, Vincent-Delorme C, Echenne B, Simon-Bouy B, Kleefstra T, Willemsen M, Fryns JP, Devriendt K, Ullmann R, Vingron M, Wrogemann K, Wienker TF, Tzschach A, van Bokhoven H, Gecz J, Jentsch TJ, Chen W, Ropers HH, Kalscheuer VM. X-exome sequencing of 405 unresolved families identifies seven novel intellectual disability genes. Mol Psychiatry 2016; 21:133-48. [PMID: 25644381 PMCID: PMC5414091 DOI: 10.1038/mp.2014.193] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 11/17/2014] [Accepted: 12/08/2014] [Indexed: 12/27/2022]
Abstract
X-linked intellectual disability (XLID) is a clinically and genetically heterogeneous disorder. During the past two decades in excess of 100 X-chromosome ID genes have been identified. Yet, a large number of families mapping to the X-chromosome remained unresolved suggesting that more XLID genes or loci are yet to be identified. Here, we have investigated 405 unresolved families with XLID. We employed massively parallel sequencing of all X-chromosome exons in the index males. The majority of these males were previously tested negative for copy number variations and for mutations in a subset of known XLID genes by Sanger sequencing. In total, 745 X-chromosomal genes were screened. After stringent filtering, a total of 1297 non-recurrent exonic variants remained for prioritization. Co-segregation analysis of potential clinically relevant changes revealed that 80 families (20%) carried pathogenic variants in established XLID genes. In 19 families, we detected likely causative protein truncating and missense variants in 7 novel and validated XLID genes (CLCN4, CNKSR2, FRMPD4, KLHL15, LAS1L, RLIM and USP27X) and potentially deleterious variants in 2 novel candidate XLID genes (CDK16 and TAF1). We show that the CLCN4 and CNKSR2 variants impair protein functions as indicated by electrophysiological studies and altered differentiation of cultured primary neurons from Clcn4(-/-) mice or after mRNA knock-down. The newly identified and candidate XLID proteins belong to pathways and networks with established roles in cognitive function and intellectual disability in particular. We suggest that systematic sequencing of all X-chromosomal genes in a cohort of patients with genetic evidence for X-chromosome locus involvement may resolve up to 58% of Fragile X-negative cases.
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Affiliation(s)
- H Hu
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - S A Haas
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - J Chelly
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - H Van Esch
- Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - M Raynaud
- Inserm U930 ‘Imaging and Brain', Tours, France,University François-Rabelais, Tours, France,Centre Hospitalier Régional Universitaire, Service de Génétique, Tours, France
| | - A P M de Brouwer
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - S Weinert
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany,Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
| | - G Froyen
- Human Genome Laboratory, VIB Center for the Biology of Disease, Leuven, Belgium,Human Genome Laboratory, Department of Human Genetics, K.U. Leuven, Leuven, Belgium
| | - S G M Frints
- Department of Clinical Genetics, Maastricht University Medical Center, azM, Maastricht, The Netherlands,School for Oncology and Developmental Biology, GROW, Maastricht University, Maastricht, The Netherlands
| | - F Laumonnier
- Inserm U930 ‘Imaging and Brain', Tours, France,University François-Rabelais, Tours, France
| | - T Zemojtel
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - M I Love
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - H Richard
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - A-K Emde
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - M Bienek
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - C Jensen
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - M Hambrock
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - U Fischer
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - C Langnick
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany
| | - M Feldkamp
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany
| | - W Wissink-Lindhout
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - N Lebrun
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - L Castelnau
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - J Rucci
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - R Montjean
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - O Dorseuil
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - P Billuart
- University Paris Descartes, Paris, France,Centre National de la Recherche Scientifique Unité Mixte de Recherche 8104, Institut National de la Santé et de la Recherche Médicale Unité 1016, Institut Cochin, Paris, France
| | - T Stuhlmann
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany,Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
| | - M Shaw
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - M A Corbett
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - A Gardner
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - S Willis-Owen
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,National Heart and Lung Institute, Imperial College London, London, UK
| | - C Tan
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia
| | - K L Friend
- SA Pathology, Women's and Children's Hospital, Adelaide, SA, Australia
| | - S Belet
- Human Genome Laboratory, VIB Center for the Biology of Disease, Leuven, Belgium,Human Genome Laboratory, Department of Human Genetics, K.U. Leuven, Leuven, Belgium
| | - K E P van Roozendaal
- Department of Clinical Genetics, Maastricht University Medical Center, azM, Maastricht, The Netherlands,School for Oncology and Developmental Biology, GROW, Maastricht University, Maastricht, The Netherlands
| | - M Jimenez-Pocquet
- Centre Hospitalier Régional Universitaire, Service de Génétique, Tours, France
| | - M-P Moizard
- Inserm U930 ‘Imaging and Brain', Tours, France,University François-Rabelais, Tours, France,Centre Hospitalier Régional Universitaire, Service de Génétique, Tours, France
| | - N Ronce
- Inserm U930 ‘Imaging and Brain', Tours, France,University François-Rabelais, Tours, France,Centre Hospitalier Régional Universitaire, Service de Génétique, Tours, France
| | - R Sun
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - S O'Keeffe
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - R Chenna
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - A van Bömmel
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - J Göke
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - A Hackett
- Genetics of Learning and Disability Service, Hunter Genetics, Waratah, NSW, Australia
| | - M Field
- Genetics of Learning and Disability Service, Hunter Genetics, Waratah, NSW, Australia
| | - L Christie
- Genetics of Learning and Disability Service, Hunter Genetics, Waratah, NSW, Australia
| | - J Boyle
- Genetics of Learning and Disability Service, Hunter Genetics, Waratah, NSW, Australia
| | - E Haan
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,SA Pathology, Women's and Children's Hospital, Adelaide, SA, Australia
| | - J Nelson
- Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, WA, Australia
| | - G Turner
- Genetics of Learning and Disability Service, Hunter Genetics, Waratah, NSW, Australia
| | - G Baynam
- Genetic Services of Western Australia, King Edward Memorial Hospital, Perth, WA, Australia,School of Paediatrics and Child Health, University of Western Australia, Perth, WA, Australia,Institute for Immunology and Infectious Diseases, Murdoch University, Perth, WA, Australia,Telethon Kids Institute, Perth, WA, Australia
| | | | - U Müller
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany,bio.logis Center for Human Genetics, Frankfurt a. M., Germany
| | - D Steinberger
- Institut für Humangenetik, Justus-Liebig-Universität Giessen, Giessen, Germany,bio.logis Center for Human Genetics, Frankfurt a. M., Germany
| | - B Budny
- Chair and Department of Endocrinology, Metabolism and Internal Diseases, Ponzan University of Medical Sciences, Poznan, Poland
| | - M Badura-Stronka
- Chair and Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - A Latos-Bieleńska
- Chair and Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - L B Ousager
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - P Wieacker
- Institut für Humangenetik, Universitätsklinikum Münster, Muenster, Germany
| | | | - M-L Bondeson
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - G Annerén
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - A Dufke
- Institut für Medizinische Genetik und Angewandte Genomik, Tübingen, Germany
| | - M Cohen
- Kinderzentrum München, München, Germany
| | - L Van Maldergem
- Centre de Génétique Humaine, Université de Franche-Comté, Besançon, France
| | - C Vincent-Delorme
- Service de Génétique, Hôpital Jeanne de Flandre CHRU de Lilles, Lille, France
| | - B Echenne
- Service de Neuro-Pédiatrie, CHU Montpellier, Montpellier, France
| | - B Simon-Bouy
- Laboratoire SESEP, Centre hospitalier de Versailles, Le Chesnay, France
| | - T Kleefstra
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - M Willemsen
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - J-P Fryns
- Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - K Devriendt
- Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium
| | - R Ullmann
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - M Vingron
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - K Wrogemann
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany,Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, MB, Canada
| | - T F Wienker
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - A Tzschach
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - H van Bokhoven
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - J Gecz
- School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, SA, Australia,Robinson Research Institute, The University of Adelaide, Adelaide, SA, Australia
| | - T J Jentsch
- Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany,Leibniz-Institut für Molekulare Pharmakologie, Berlin, Germany
| | - W Chen
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany,Max-Delbrück-Centrum für Molekulare Medizin, Berlin, Germany
| | - H-H Ropers
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - V M Kalscheuer
- Department of Human Molecular Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany,Max Planck Institute for Molecular Genetics, Ihnestrasse 73, Berlin 14195, Germany. E-mail:
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Spinal muscular atrophy with respiratory distress type 1 (SMARD1) Report of a Spanish case with extended clinicopathological follow-up. Clin Neuropathol 2015; 35:58-65. [PMID: 26709713 PMCID: PMC4806405 DOI: 10.5414/np300902] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2016] [Indexed: 12/02/2022] Open
Abstract
Background: Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a clinically and genetically distinct and uncommon variant of SMA that results from irreversible degeneration of α-motor neurons in the anterior horns of the spinal cord and in ganglion cells on the spinal root ganglia. Aims: To describe the clinical, electrophysiological, neuropathological, and genetic findings, at different stages from birth to death, of a Spanish child diagnosed with SMARD1. Patient and methods: We report the case of a 3-month-old girl with severe respiratory insufficiency and, later, intense hypotonia. Paraclinical tests included biochemistry, chest X-ray, and electrophysiological studies, among others. Muscle and nerve biopsies were performed at 5 and 10 months and studied under light and electron microscopy. Post-mortem examination and genetic investigations were performed. Results: Pre- and post-mortem histopathological findings demonstrated the disease progression over time. Muscle biopsy at 5 months of age was normal, however a marked neurogenic atrophy was present in post-mortem samples. Peripheral motor and sensory nerves were severely involved likely due to a primary axonal disorder. Automatic sequencing of IGHMBP2 revealed a compound heterozygous mutation. Conclusions: The diagnosis of SMARD1 should be considered in children with early respiratory insufficiency or in cases of atypical SMA. Direct sequencing of the IGHMBP2 gene should be performed.
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Capuano A, Bucciotti F, Farwell KD, Tippin Davis B, Mroske C, Hulick PJ, Weissman SM, Gao Q, Spessotto P, Colombatti A, Doliana R. Diagnostic Exome Sequencing Identifies a Novel Gene, EMILIN1, Associated with Autosomal-Dominant Hereditary Connective Tissue Disease. Hum Mutat 2015; 37:84-97. [PMID: 26462740 PMCID: PMC4738430 DOI: 10.1002/humu.22920] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 10/05/2015] [Indexed: 12/31/2022]
Abstract
Heritable connective tissue diseases are a highly heterogeneous family of over 200 disorders that affect the extracellular matrix. While the genetic basis of several disorders is established, the etiology has not been discovered for a large portion of patients, likely due to rare yet undiscovered disease genes. By performing trio‐exome sequencing of a 55‐year‐old male proband presenting with multiple symptoms indicative of a connective disorder, we identified a heterozygous missense alteration in exon 1 of the Elastin Microfibril Interfacer 1 (EMILIN1) gene, c.64G>A (p.A22T). The proband presented with ascending and descending aortic aneurysms, bilateral lower leg and foot sensorimotor peripheral neuropathy, arthropathy, and increased skin elasticity. Sanger sequencing confirmed that the EMILIN1 alteration, which maps around the signal peptide cleavage site, segregated with disease in the affected proband, mother, and son. The impaired secretion of EMILIN‐1 in cells transfected with the mutant p.A22T coincided with abnormal protein accumulation within the endoplasmic reticulum. In skin biopsy of the proband, we detected less EMILIN‐1 with disorganized and abnormal coarse fibrils, aggregated deposits underneath the epidermis basal lamina, and dermal cells apoptosis. These findings collectively suggest that EMILIN1 may represent a new disease gene associated with an autosomal‐dominant connective tissue disorder.
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Affiliation(s)
- Alessandra Capuano
- Department of Translational Research, CRO-IRCCS National Cancer Institute, Aviano, 33081, Italy
| | - Francesco Bucciotti
- Department of Translational Research, CRO-IRCCS National Cancer Institute, Aviano, 33081, Italy
| | | | | | | | - Peter J Hulick
- Center for Medical Genetics, NorthShore University HealthSystem, Evanston, Illinois, 60201
| | - Scott M Weissman
- Center for Medical Genetics, NorthShore University HealthSystem, Evanston, Illinois, 60201
| | - Qingshen Gao
- NorthShore Research Institute, NorthShore University HealthSystem, Evanston, Illinois, 60201
| | - Paola Spessotto
- Department of Translational Research, CRO-IRCCS National Cancer Institute, Aviano, 33081, Italy
| | - Alfonso Colombatti
- Department of Translational Research, CRO-IRCCS National Cancer Institute, Aviano, 33081, Italy
| | - Roberto Doliana
- Department of Translational Research, CRO-IRCCS National Cancer Institute, Aviano, 33081, Italy
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Schottmann G, Seelow D, Seifert F, Morales-Gonzalez S, Gill E, von Au K, von Moers A, Stenzel W, Schuelke M. Recessive REEP1 mutation is associated with congenital axonal neuropathy and diaphragmatic palsy. NEUROLOGY-GENETICS 2015; 1:e32. [PMID: 27066569 PMCID: PMC4811389 DOI: 10.1212/nxg.0000000000000032] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 09/08/2015] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To identify the underlying genetic cause of a congenital neuropathy in a 5-year-old boy as part of a cohort of 32 patients from 23 families with genetically unresolved neuropathies. METHODS We used autozygosity mapping coupled with next-generation sequencing to investigate a consanguineous family from Lebanon with 1 affected and 2 healthy children. Variants were investigated for segregation in the family by Sanger sequencing. A splice site mutation was further evaluated on the messenger RNA level by quantitative reverse transcription PCR. Subsequently, a larger cohort was specifically screened for receptor expression-enhancing protein 1 (REEP1) gene mutations. RESULTS We detected a homozygous splice donor mutation in REEP1 (c.303+1-7GTAATAT>AC, p.F62Kfs23*; NM_022912) that cosegregated with the phenotype in the family, leading to complete skipping of exon 4 and a premature stop codon. The phenotype of the patient is similar to spinal muscular atrophy with respiratory distress type 1 (SMARD1) with additional distal arthrogryposis and involvement of the upper motor neuron manifested by pronounced hyperreflexia. CONCLUSION To date, only dominant REEP1 mutations have been reported to be associated with a slowly progressive hereditary spastic paraplegia. The findings from our patient expand the phenotypical spectrum and the mode of inheritance of REEP1-associated disorders. Recessive mutations in REEP1 should be considered in the molecular genetic workup of patients with a neuromuscular disorder resembling SMARD1, especially if additional signs of upper motor neuron involvement and distal arthrogryposis are present.
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Affiliation(s)
- Gudrun Schottmann
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Dominik Seelow
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Franziska Seifert
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Susanne Morales-Gonzalez
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Esther Gill
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Katja von Au
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Arpad von Moers
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Werner Stenzel
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
| | - Markus Schuelke
- Departments of Neuropediatrics (G.S., D.S., F.S., S.M.-G., E.G., M.S.) and Neuropediatrics/SPZ (K.v.A.), NeuroCure Clinical Research Center, Charité-Universitätsmedizin, Berlin, Germany; the Department of Neuropathology (W.S.), Charité-Universitätsmedizin Berlin, Germany; and the DRK Children's Hospital Berlin (A.v.M.), Germany
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Murray LM, Beauvais A, Gibeault S, Courtney NL, Kothary R. Transcriptional profiling of differentially vulnerable motor neurons at pre-symptomatic stage in the Smn (2b/-) mouse model of spinal muscular atrophy. Acta Neuropathol Commun 2015; 3:55. [PMID: 26374403 PMCID: PMC4570693 DOI: 10.1186/s40478-015-0231-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 08/10/2015] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION The term motor neuron disease encompasses a spectrum of disorders in which motor neurons are the lost. Importantly, while some motor neurons are lost early in disease and others remain intact at disease end-stage. This creates a valuable experimental paradigm to investigate the factors that regulate motor neuron vulnerability. Spinal muscular atrophy is a childhood motor neuron disease caused by mutations or deletions in the SMN1 gene. Here, we have performed transcriptional analysis on differentially vulnerable motor neurons from an intermediate mouse model of Spinal muscular atrophy at a presymptomatic time point. RESULTS We have characterised two differentially vulnerable populations, differing in the level neuromuscular junction loss. Transcriptional analysis on motor neuron cell bodies revealed that reduced Smn levels correlate with a reduction of transcripts associated with the ribosome, rRNA binding, ubiquitination and oxidative phosphorylation. Furthermore, P53 pathway activation precedes neuromuscular junction loss, suggesting that denervation may be a consequence, rather than a cause of motor neuron death in Spinal muscular atrophy. Finally, increased vulnerability correlates with a decrease in the positive regulation of DNA repair. CONCLUSIONS This study identifies pathways related to the function of Smn and associated with differential motor unit vulnerability, thus presenting a number of exciting targets for future therapeutic development.
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Alamillo CL, Powis Z, Farwell K, Shahmirzadi L, Weltmer EC, Turocy J, Lowe T, Kobelka C, Chen E, Basel D, Ashkinadze E, D'Augelli L, Chao E, Tang S. Exome sequencing positively identified relevant alterations in more than half of cases with an indication of prenatal ultrasound anomalies. Prenat Diagn 2015; 35:1073-8. [PMID: 26147564 DOI: 10.1002/pd.4648] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Exome sequencing is a successful option for diagnosing individuals with previously uncharacterized genetic conditions, however little has been reported regarding its utility in a prenatal setting. The goal of this study is to describe the results from a cohort of fetuses for which exome sequencing was performed. METHODS We performed a retrospective analysis of the first seven cases referred to our laboratory for exome sequencing following fetal demise or termination of pregnancy. All seven pregnancies had multiple congenital anomalies identified by level II ultrasound. Exome sequencing was performed on trios using cultured amniocytes or products of conception from the affected fetuses. RESULTS Relevant alterations were identified in more than half of the cases (4/7). Three of the four were categorized as 'positive' results, and one of the four was categorized as a 'likely positive' result. The provided diagnoses included osteogenesis imperfecta II (COL1A2), glycogen storage disease IV (GBE1), oral-facial-digital syndrome 1 (OFD1), and RAPSN-associated fetal akinesia deformation sequence. CONCLUSION This data suggests that exome sequencing is likely to be a valuable diagnostic testing option for pregnancies with multiple congenital anomalies detected by prenatal ultrasound; however, additional studies with larger cohorts of affected pregnancies are necessary to confirm these findings.
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Affiliation(s)
| | - Zöe Powis
- Ambry Genetics, Aliso Viejo, CA, USA
| | | | | | | | - John Turocy
- Genetics Department, Kaiser Permanente, Clovis, CA, USA
| | - Thomas Lowe
- Thomas Lowe, MD, Private Practice, Boca Raton, FL, USA
| | | | - Emily Chen
- Genetics Department, Kaiser Permanente, San Francisco, CA, USA
| | - Donald Basel
- Division of Genetics, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Elena Ashkinadze
- Division of Maternal-Fetal Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | | | - Elizabeth Chao
- Ambry Genetics, Aliso Viejo, CA, USA.,Department of Pediatrics, University of California Irvine, Irvine, CA, USA
| | - Sha Tang
- Ambry Genetics, Aliso Viejo, CA, USA
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Abstract
Spinal muscular atrophies (SMAs) are a group of inherited disorders characterized by motor neuron loss in the spinal cord and lower brainstem, muscle weakness, and atrophy. The clinical and genetic phenotypes incorporate a wide spectrum that is differentiated based on age of onset, pattern of muscle involvement, and inheritance pattern. Over the past several years, rapid advances in genetic technology have accelerated the identification of causative genes and provided important advances in understanding the molecular and biological basis of SMA and insights into the selective vulnerability of the motor neuron. Common pathophysiological themes include defects in RNA metabolism and splicing, axonal transport, and motor neuron development and connectivity. Together these have revealed potential novel treatment strategies, and extensive efforts are being undertaken towards expedited therapeutics. While a number of promising therapies for SMA are emerging, defining therapeutic windows and developing sensitive and relevant biomarkers are critical to facilitate potential success in clinical trials. This review incorporates an overview of the clinical manifestations and genetics of SMA, and describes recent advances in the understanding of mechanisms of disease pathogenesis and development of novel treatment strategies.
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Affiliation(s)
- Michelle A. Farrar
- />Discipline of Paediatrics, School of Women’s and Children’s Health, UNSW Medicine, The University of New South Wales, Sydney, Australia
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Department of Neurology, Sydney Children’s Hospital, Randwick, NSW 2031 Australia
| | - Matthew C. Kiernan
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Brain & Mind Research Institute, University of Sydney, Sydney, Australia
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The ribosome biogenesis factor Nol11 is required for optimal rDNA transcription and craniofacial development in Xenopus. PLoS Genet 2015; 11:e1005018. [PMID: 25756904 PMCID: PMC4354908 DOI: 10.1371/journal.pgen.1005018] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 01/22/2015] [Indexed: 01/30/2023] Open
Abstract
The production of ribosomes is ubiquitous and fundamental to life. As such, it is surprising that defects in ribosome biogenesis underlie a growing number of symptomatically distinct inherited disorders, collectively called ribosomopathies. We previously determined that the nucleolar protein, NOL11, is essential for optimal pre-rRNA transcription and processing in human tissue culture cells. However, the role of NOL11 in the development of a multicellular organism remains unknown. Here, we reveal a critical function for NOL11 in vertebrate ribosome biogenesis and craniofacial development. Nol11 is strongly expressed in the developing cranial neural crest (CNC) of both amphibians and mammals, and knockdown of Xenopus nol11 results in impaired pre-rRNA transcription and processing, increased apoptosis, and abnormal development of the craniofacial cartilages. Inhibition of p53 rescues this skeletal phenotype, but not the underlying ribosome biogenesis defect, demonstrating an evolutionarily conserved control mechanism through which ribosome-impaired craniofacial cells are removed. Excessive activation of this mechanism impairs craniofacial development. Together, our findings reveal a novel requirement for Nol11 in craniofacial development, present the first frog model of a ribosomopathy, and provide further insight into the clinically important relationship between specific ribosome biogenesis proteins and craniofacial cell survival.
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