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Bolano-Díaz C, Verdú-Díaz J, Díaz-Manera J. MRI for the diagnosis of limb girdle muscular dystrophies. Curr Opin Neurol 2024; 37:536-548. [PMID: 39132784 DOI: 10.1097/wco.0000000000001305] [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: 08/13/2024]
Abstract
PURPOSE OF REVIEW In the last 30 years, there have many publications describing the pattern of muscle involvement of different neuromuscular diseases leading to an increase in the information available for diagnosis. A high degree of expertise is needed to remember all the patterns described. Some attempts to use artificial intelligence or analysing muscle MRIs have been developed. We review the main patterns of involvement in limb girdle muscular dystrophies (LGMDs) and summarize the strategies for using artificial intelligence tools in this field. RECENT FINDINGS The most frequent LGMDs have a widely described pattern of muscle involvement; however, for those rarer diseases, there is still not too much information available. patients. Most of the articles still include only pelvic and lower limbs muscles, which provide an incomplete picture of the diseases. AI tools have efficiently demonstrated to predict diagnosis of a limited number of disease with high accuracy. SUMMARY Muscle MRI continues being a useful tool supporting the diagnosis of patients with LGMD and other neuromuscular diseases. However, the huge variety of patterns described makes their use in clinics a complicated task. Artificial intelligence tools are helping in that regard and there are already some accessible machine learning algorithms that can be used by the global medical community.
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Affiliation(s)
- Carla Bolano-Díaz
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - José Verdú-Díaz
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Jordi Díaz-Manera
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
- Neuromuscular Diseases Laboratory, Insitut de Recerca de l'Hospital de la Santa Creu i Sant Pau
- Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Barcelona, Spain
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2
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Alawneh I, Stosic A, Gonorazky H. Muscle MRI patterns for limb girdle muscle dystrophies: systematic review. J Neurol 2023:10.1007/s00415-023-11722-1. [PMID: 37129643 DOI: 10.1007/s00415-023-11722-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/06/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023]
Abstract
Limb girdle muscle dystrophies (LGMDs) are a group of inherited neuromuscular disorders comprising more than 20 genes. There have been increasing efforts to characterize this group with Muscle MRI. However, due to the complexity and similarities, the interpretation of the MRI patterns is usually done by experts in the field. Here, we proposed a step-by-step image interpretation of Muscle MRI in LGDM by evaluating the variability of muscle pattern involvement reported in the literature. A systematic review with an open start date to November 2022 was conducted to describe all LGMDs' muscle MRI patterns. Eighty-eight studies were included in the final review. Data were found to describe muscle MRI patterns for 15 out of 17 LGMDs types. Although the diagnosis of LGMDs is challenging despite the advanced genetic testing and other diagnostic modalities, muscle MRI is shown to help in the diagnosis of LGMDs. To further increase the yield for muscle MRI in the neuromuscular field, larger cohorts of patients need to be conducted.
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Affiliation(s)
- Issa Alawneh
- Department of Neurology, The Hospital for Sick Children, Toronto, Canada
| | - Ana Stosic
- Genetics and Genome Biology Program, The Hospital for Sick Children Research Institute, Toronto, Canada
| | - Hernan Gonorazky
- Department of Neurology, The Hospital for Sick Children, Toronto, Canada.
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3
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Poyatos-García J, Blázquez-Bernal Á, Selva-Giménez M, Bargiela A, Espinosa-Espinosa J, Vázquez-Manrique RP, Bigot A, Artero R, Vilchez JJ. CRISPR-Cas9 editing of a TNPO3 mutation in a muscle cell model of limb-girdle muscular dystrophy type D2. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 31:324-338. [PMID: 36789274 PMCID: PMC9898580 DOI: 10.1016/j.omtn.2023.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 01/06/2023] [Indexed: 01/13/2023]
Abstract
A single-nucleotide deletion in the stop codon of the nuclear import receptor transportin-3 (TNPO3), also involved in human immunodeficiency virus type 1 (HIV-1) infection, causes the ultrarare autosomal dominant disease limb-girdle muscular dystrophy D2 (LGMDD2) by extending the wild-type protein. Here, we generated a patient-derived in vitro model of LGMDD2 as an immortalized myoblast cell line carrying the TNP O 3 mutation. The cell model reproduced critical molecular alterations seen in patients, such as TNP O 3 overexpression, defects in terminal muscle markers, and autophagy overactivation. Correction of the TNP O 3 mutation via CRISPR-Cas9 editing caused a significant reversion of the pathological phenotypes in edited cells, including a complete absence of the mutant TNPO3 protein, as detected with a polyclonal antibody specific against the abnormal 15-aa peptide. Transcriptomic analyses found that 15% of the transcriptome was differentially expressed in model myotubes. CRISPR-Cas9-corrected cells showed that 44% of the alterations were rescued toward normal levels. MicroRNAs (miRNAs) analyses showed that around 50% of miRNAs with impaired expression because of the disease were recovered on the mutation edition. In summary, this work provides proof of concept of the potential of CRISPR-Cas9-mediated gene editing of TNP O 3 as a therapeutic approach and describes critical reagents in LGMDD2 research.
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Affiliation(s)
- Javier Poyatos-García
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), U763, CB06/05/0091, 46026 Valencia, Spain
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital La Fe (IIS La Fe), 46026 Valencia, Spain
| | - Águeda Blázquez-Bernal
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Burjasot, 46100 Valencia, Spain
- INCLIVA Biomedical Research Institute, 46010 Valencia, Spain
| | - Marta Selva-Giménez
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), U763, CB06/05/0091, 46026 Valencia, Spain
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital La Fe (IIS La Fe), 46026 Valencia, Spain
| | - Ariadna Bargiela
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital La Fe (IIS La Fe), 46026 Valencia, Spain
| | - Jorge Espinosa-Espinosa
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Burjasot, 46100 Valencia, Spain
- INCLIVA Biomedical Research Institute, 46010 Valencia, Spain
| | - Rafael P. Vázquez-Manrique
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), U763, CB06/05/0091, 46026 Valencia, Spain
- Grupo de Investigación en Biomedicina Molecular, Celular y Genómica, Instituto de Investigación Sanitaria La Fe (IIS La Fe), 46026 Valencia, Spain
- Joint Unit for Rare Diseases IIS La Fe-CIPF, 46012 Valencia, Spain
| | - Anne Bigot
- Sorbonne Université, INSERM, Institut de Myologie, Centre de Recherche en Myologie, 75013 Paris, France
| | - Ruben Artero
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Burjasot, 46100 Valencia, Spain
- INCLIVA Biomedical Research Institute, 46010 Valencia, Spain
| | - Juan Jesús Vilchez
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), U763, CB06/05/0091, 46026 Valencia, Spain
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital La Fe (IIS La Fe), 46026 Valencia, Spain
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4
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Diez-Fuertes F, López-Huertas MR, García-Pérez J, Calonge E, Bermejo M, Mateos E, Martí P, Muelas N, Vílchez JJ, Coiras M, Alcamí J, Rodríguez-Mora S. Transcriptomic Evidence of the Immune Response Activation in Individuals With Limb Girdle Muscular Dystrophy Dominant 2 (LGMDD2) Contributes to Resistance to HIV-1 Infection. Front Cell Dev Biol 2022; 10:839813. [PMID: 35646913 PMCID: PMC9136291 DOI: 10.3389/fcell.2022.839813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
LGMDD2 is a rare form of muscular dystrophy characterized by one of the three heterozygous deletions described within the TNPO3 gene that result in the addition of a 15-amino acid tail in the C-terminus.TNPO3 is involved in the nuclear import of splicing factors and acts as a host cofactor for HIV-1 infection by mechanisms not yet deciphered. Further characterization of the crosstalk between HIV-1 infection and LGMDD2 disease may contribute to a better understanding of both the cellular alterations occurring in LGMDD2 patients and the role of TNPO3 in the HIV-1 cycle. To this regard, transcriptome profiling of PBMCs from LGMDD2 patients carrying the deletion c.2771delA in the TNPO3 gene was compared to healthy controls. A total of 545 differentially expressed genes were detected between LGMDD2 patients and healthy controls, with a high representation of G protein-coupled receptor binding chemokines and metallopeptidases among the most upregulated genes in LGMDD2 patients. Plasma levels of IFN-β and IFN-γ were 4.7- and 2.7-fold higher in LGMDD2 patients, respectively. An increase of 2.3-fold in the expression of the interferon-stimulated gene MxA was observed in activated PBMCs from LGMDD2 patients after ex vivo HIV-1 pseudovirus infection. Thus, the analysis suggests a pro-inflammatory state in LGMDD2 patients also described for other muscular dystrophies, that is characterized by the alteration of IL-17 signaling pathway and the consequent increase of metallopeptidases activity and TNF response. In summary, the increase in interferons and inflammatory mediators suggests an antiviral environment and resistance to HIV-1 infection but that could also impair muscular function in LGMDD2 patients, worsening disease evolution. Biomarkers of disease progression and therapeutic strategies based on these genes and mechanisms should be further investigated for this type of muscular dystrophy.
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Affiliation(s)
- Francisco Diez-Fuertes
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - María Rosa López-Huertas
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Javier García-Pérez
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Esther Calonge
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Mercedes Bermejo
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Elena Mateos
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - Pilar Martí
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari i Politècnic La Fe, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Nuria Muelas
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari i Politècnic La Fe, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Juan Jesús Vílchez
- Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari i Politècnic La Fe, Valencia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Mayte Coiras
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
| | - José Alcamí
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
- Infectious Diseases Unit, IDIBAPS, Hospital Clinic, University of Barcelona, Barcelona, Spain
- *Correspondence: José Alcamí, ; Sara Rodríguez-Mora,
| | - Sara Rodríguez-Mora
- AIDS Immunopathogenesis Unit, National Center of Microbiology, Instituto de Salud Carlos III, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Madrid, Spain
- *Correspondence: José Alcamí, ; Sara Rodríguez-Mora,
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Costa R, Rodia MT, Pacilio S, Angelini C, Cenacchi G. LGMD D2 TNPO3-Related: From Clinical Spectrum to Pathogenetic Mechanism. Front Neurol 2022; 13:840683. [PMID: 35309568 PMCID: PMC8931187 DOI: 10.3389/fneur.2022.840683] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Limb-girdle muscular dystrophies (LGMDs) are clinically and genetically heterogeneous diseases presenting with a wide clinical spectrum. Autosomal dominant LGMDs represent about 10–15% of LGMDs and include disorders due to defects of DNAJB6, transportin-3 (TNPO3), HNRNPDL, Calpain-3 (CAPN3), and Bethlem myopathy. This review article aims to describe the clinical spectrum of LGMD D2 TNPO3-related, a rare disease due to heterozygous mutation in the TNPO3 gene. TNPO3 encodes for transportin-3, which belongs to the importin beta family and transports into the nucleus serine/arginine-rich (SR) proteins, such as splicing factors, and HIV-1 proteins, thus contributing to viral infection. The purpose of this review is to present and compare the clinical features and the genetic and histopathological findings described in LGMD D2, performing a comparative analytical description of all the families and sporadic cases identified. Even if the causative gene and mutations of this disease have been identified, the pathogenic mechanisms are still an open issue; therefore, we will present an overview of the hypotheses that explain the pathology of LGMD D2 TNPO3-related.
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Affiliation(s)
- Roberta Costa
- Department of Biomedical and Neuromotor Sciences–DIBINEM, Alma Mater Studiorum University of Bologna, Bologna, Italy
- Applied Biomedical Research Center–CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Maria Teresa Rodia
- Department of Biomedical and Neuromotor Sciences–DIBINEM, Alma Mater Studiorum University of Bologna, Bologna, Italy
- Applied Biomedical Research Center–CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Serafina Pacilio
- Department of Biomedical and Neuromotor Sciences–DIBINEM, Alma Mater Studiorum University of Bologna, Bologna, Italy
- Applied Biomedical Research Center–CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Corrado Angelini
- Laboratory for Neuromuscular Diseases, Campus Pietro d'Abano, University of Padova, Padova, Italy
| | - Giovanna Cenacchi
- Department of Biomedical and Neuromotor Sciences–DIBINEM, Alma Mater Studiorum University of Bologna, Bologna, Italy
- Applied Biomedical Research Center–CRBA, IRCCS St. Orsola Hospital, Alma Mater Studiorum University of Bologna, Bologna, Italy
- *Correspondence: Giovanna Cenacchi
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6
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Blázquez-Bernal Á, Fernandez-Costa JM, Bargiela A, Artero R. Inhibition of autophagy rescues muscle atrophy in a LGMDD2 Drosophila model. FASEB J 2021; 35:e21914. [PMID: 34547132 DOI: 10.1096/fj.202100539rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 01/18/2023]
Abstract
Limb-girdle muscular dystrophy D2 (LGMDD2) is an ultrarare autosomal dominant myopathy caused by mutation of the normal stop codon of the TNPO3 nuclear importin. The mutant protein carries a 15 amino acid C-terminal extension associated with pathogenicity. Here we report the first animal model of the disease by expressing the human mutant TNPO3 gene in Drosophila musculature or motor neurons and concomitantly silencing the endogenous expression of the fly protein ortholog. A similar genotype expressing wildtype TNPO3 served as a control. Phenotypes characterization revealed that mutant TNPO3 expression targeted at muscles or motor neurons caused LGMDD2-like phenotypes such as muscle degeneration and atrophy, and reduced locomotor ability. Notably, LGMDD2 mutation increase TNPO3 at the transcript and protein level in the Drosophila model Upregulated muscle autophagy observed in LGMDD2 patients was also confirmed in the fly model, in which the anti-autophagic drug chloroquine was able to rescue histologic and functional phenotypes. Overall, we provide a proof of concept of autophagy as a target to treat disease phenotypes and propose a neurogenic component to explain mutant TNPO3 pathogenicity in diseased muscles.
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Affiliation(s)
- Águeda Blázquez-Bernal
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain.,Area of Metabolism and Organic Failure, Incliva Health Research Institute, Valencia, Spain.,Incliva-CIPF Joint Unit, Valencia, Spain
| | - Juan M Fernandez-Costa
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain.,Area of Metabolism and Organic Failure, Incliva Health Research Institute, Valencia, Spain.,Incliva-CIPF Joint Unit, Valencia, Spain
| | - Ariadna Bargiela
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain.,Area of Metabolism and Organic Failure, Incliva Health Research Institute, Valencia, Spain.,Incliva-CIPF Joint Unit, Valencia, Spain
| | - Ruben Artero
- Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain.,Area of Metabolism and Organic Failure, Incliva Health Research Institute, Valencia, Spain.,Incliva-CIPF Joint Unit, Valencia, Spain
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7
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Transportin 3 (TNPO3) and related proteins in limb girdle muscular dystrophy D2 muscle biopsies: A morphological study and pathogenetic hypothesis. Neuromuscul Disord 2020; 30:685-692. [PMID: 32690349 DOI: 10.1016/j.nmd.2020.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/05/2020] [Accepted: 05/18/2020] [Indexed: 11/22/2022]
Abstract
LGMD D2 is a disease caused by TNPO3 mutation. We describe the expression of TNPO3 and selected proteins, likely modified by TNPO3 mutation, in muscle biopsies of affected patients. We also aim to find other genes involved in pathways correlated to TNPO3. Our morphological study on LGMD D2 muscle described the expression of TNPO3 and SRSF1, a splicing factor transported by TNPO3. Moreover, we investigated some sarcomeric and nuclear proteins, likely altered by TNPO3 mutation. Through an in silico approach we tried to identify genes involved in pathways that include, besides TNPO3 and SRSF1, p62 and Murf-1, altered in LGMD D2. In patients' muscles TNPO3 appeared weaker and randomly organized, with sporadic cytoplasmic aggregates positive for TNPO3; both SRSF1 and sarcomeric alpha actinin showed a different expression, while there were no alterations in the expression of the nuclear proteins. The in silico study lead to identify five genes, all coding for proteins responsible for muscle contraction. Our data suggest a possible interference in the morphology and function of myofibrillar network by mutated TNPO3; these findings are supported by the in silico identification of genes involved in muscle contraction that could help to explain the pathogenic mechanisms of LGMD D2.
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Angelini C, Pegoraro V, Cenacchi G. The clinical and molecular spectrum of autosomal dominant limb-girdle muscular dystrophies focusing on transportinopathy. Expert Opin Orphan Drugs 2019. [DOI: 10.1080/21678707.2019.1622412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | | | - Giovanna Cenacchi
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum–University of Bologna, Bologna, Italy
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9
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Vihola A, Palmio J, Danielsson O, Penttilä S, Louiselle D, Pittman S, Weihl C, Udd B. Novel mutation in TNPO3 causes congenital limb-girdle myopathy with slow progression. NEUROLOGY-GENETICS 2019; 5:e337. [PMID: 31192305 PMCID: PMC6515942 DOI: 10.1212/nxg.0000000000000337] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 03/27/2019] [Indexed: 12/03/2022]
Abstract
Objective We report a second family with autosomal dominant transportinopathy presenting with congenital or early-onset myopathy and slow progression, causing proximal and less pronounced distal muscle weakness. Methods Patients had clinical examinations, muscle MRI, EMG, and muscle biopsy studies. The MYOcap gene panel was used to identify the gene defect in the family. Muscle biopsies were used for histopathologic and protein expression studies, and TNPO3 constructs were used to study the effect of the mutations in transfected cells. Results We identified a novel heterozygous mutation, c.2757delC, in the last part of the transportin-3 (TNPO3) gene in the affected family members. The mutation causes an almost identical frameshift affecting the stop codon and elongating the C-term protein product of the TNPO3 transcript, as was previously reported in the first large Spanish-Italian LGMD1F kindred. TNPO3 protein was increased in the patient muscle and accumulated in the subsarcolemmal and perinuclear areas. At least one of the cargo proteins, the splicing factor SRRM2 was normally located in the nucleus. Transiently transfected mutant TNPO3 constructs failed to localize to cytoplasmic annulate lamellae pore complexes in cells. Conclusions We report the clinical, molecular genetic, and histopathologic features of the second transportinopathy family. The variability of the clinical phenotype together with histopathologic findings suggests that several molecular pathways may be involved in the disease pathomechanism, such as nucleocytoplasmic shuttling, protein aggregation, and defective protein turnover.
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Affiliation(s)
- Anna Vihola
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Johanna Palmio
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Olof Danielsson
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Sini Penttilä
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Daniel Louiselle
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Sara Pittman
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Conrad Weihl
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
| | - Bjarne Udd
- Folkhälsan Institute of Genetics and Department of Medical Genetics (A.V.), Medicum, University of Helsinki; Neuromuscular Research Center (J.P.), Tampere University and University Hospital of Tampere, Finland; Neuromuscular Unit (O.D.), Division of Neurology, Department of Clinical and Experimental Medicine, Linköping University, Sweden; Neuromuscular Research Center (S. Penttilä), Tampere University and University Hospital of Tampere, Finland; Department of Neurology (D.L.), Department of Neurology (S. Pittman), Department of Neurology (C.W.), Washington University School of Medicine, Saint Louis, MO; Folkhälsan Institute of Genetics and Department of Medical Genetics (B.U.), Medicum, University of Helsinki; Neuromuscular Research Center (B.U.), Tampere University and University Hospital of Tampere; and Department of Neurology (B.U.), Vaasa Central Hospital, Vaasa, Finland
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