101
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Ohno K, Ohkawara B, Ito M. Recent advances in congenital myasthenic syndromes. ACTA ACUST UNITED AC 2016. [DOI: 10.1111/cen3.12316] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Kinji Ohno
- Division of Neurogenetics; Center for Neurological Diseases and Cancer; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - Bisei Ohkawara
- Division of Neurogenetics; Center for Neurological Diseases and Cancer; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - Mikako Ito
- Division of Neurogenetics; Center for Neurological Diseases and Cancer; Nagoya University Graduate School of Medicine; Nagoya Japan
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102
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Mechanistic aspects of the formation of α-dystroglycan and therapeutic research for the treatment of α-dystroglycanopathy: A review. Mol Aspects Med 2016; 51:115-24. [PMID: 27421908 DOI: 10.1016/j.mam.2016.07.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 07/07/2016] [Accepted: 07/08/2016] [Indexed: 02/08/2023]
Abstract
α-Dystroglycanopathy, an autosomal recessive disease, is associated with the development of a variety of diseases, including muscular dystrophy. In humans, α-dystroglycanopathy includes various types of congenital muscular dystrophy such as Fukuyama type congenital muscular dystrophy (FCMD), muscle eye brain disease (MEB), and the Walker Warburg syndrome (WWS), and types of limb girdle muscular dystrophy 2I (LGMD2I). α-Dystroglycanopathy share a common etiology, since it is invariably caused by gene mutations that are associated with the O-mannose glycosylation pathway of α-dystroglycan (α-DG). α-DG is a central member of the dystrophin glycoprotein complex (DGC) family in peripheral membranes, and the proper glycosylation of α-DG is essential for it to bind to extracellular matrix proteins, such as laminin, to cell components. The disruption of this ligand-binding is thought to result in damage to cell membrane integration, leading to the development of muscular dystrophy. Clinical manifestations of α-dystroglycanopathy frequently include mild to severe alterations in the central nervous system and optical manifestations in addition to muscular dystrophy. Eighteen causative genes for α-dystroglycanopathy have been identified to date, and it is likely that more will be reported in the near future. These findings have stimulated extensive and energetic investigations in this research field, and novel glycosylation pathways have been implicated in the process. At the same time, the use of gene therapy, antisense therapy, and enzymatic supplementation have been evaluated as therapeutic possibilities for some types of α-dystroglycanopathy. Here we review the molecular and clinical findings associated with α-dystroglycanopathy and the development of therapeutic approaches, by comparing the approaches with the development of Duchenne muscular dystrophy.
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103
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Massalska D, Zimowski JG, Bijok J, Kucińska-Chahwan A, Łusakowska A, Jakiel G, Roszkowski T. Prenatal diagnosis of congenital myopathies and muscular dystrophies. Clin Genet 2016; 90:199-210. [PMID: 27197572 DOI: 10.1111/cge.12801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/05/2016] [Accepted: 05/08/2016] [Indexed: 12/14/2022]
Abstract
Congenital myopathies and muscular dystrophies constitute a genetically and phenotypically heterogeneous group of rare inherited diseases characterized by muscle weakness and atrophy, motor delay and respiratory insufficiency. To date, curative care is not available for these diseases, which may severely affect both life-span and quality of life. We discuss prenatal diagnosis and genetic counseling for families at risk, as well as diagnostic possibilities in sporadic cases.
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Affiliation(s)
- D Massalska
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - J G Zimowski
- Department of Genetics, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - J Bijok
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Kucińska-Chahwan
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Łusakowska
- Department of Neurology, Medical University of Warsaw, Poland
| | - G Jakiel
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - T Roszkowski
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
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104
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O'Grady GL, Lek M, Lamande SR, Waddell L, Oates EC, Punetha J, Ghaoui R, Sandaradura SA, Best H, Kaur S, Davis M, Laing NG, Muntoni F, Hoffman E, MacArthur DG, Clarke NF, Cooper S, North K. Diagnosis and etiology of congenital muscular dystrophy: We are halfway there. Ann Neurol 2016; 80:101-11. [PMID: 27159402 DOI: 10.1002/ana.24687] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 05/01/2016] [Accepted: 05/02/2016] [Indexed: 01/16/2023]
Abstract
OBJECTIVE To evaluate the diagnostic outcomes in a large cohort of congenital muscular dystrophy (CMD) patients using traditional and next generation sequencing (NGS) technologies. METHODS A total of 123 CMD patients were investigated using the traditional approaches of histology, immunohistochemical analysis of muscle biopsy, and candidate gene sequencing. Undiagnosed patients available for further testing were investigated using NGS. RESULTS Muscle biopsy and immunohistochemical analysis found deficiencies of laminin α2, α-dystroglycan, or collagen VI in 50% of patients. Candidate gene sequencing and chromosomal microarray established a genetic diagnosis in 32% (39 of 123). Of 85 patients presenting in the past 20 years, 28 of 51 who lacked a confirmed genetic diagnosis (55%) consented to NGS studies, leading to confirmed diagnoses in a further 11 patients. Using the combination of approaches, a confirmed genetic diagnosis was achieved in 51% (43 of 85). The diagnoses within the cohort were heterogeneous. Forty-five of 59 probands with confirmed or probable diagnoses had variants in genes known to cause CMD (76%), and 11 of 59 (19%) had variants in genes associated with congenital myopathies, reflecting overlapping features of these conditions. One patient had a congenital myasthenic syndrome, and 2 had microdeletions. Within the cohort, 5 patients had variants in novel (PIGY and GMPPB) or recently published genes (GFPT1 and MICU1), and 7 had variants in TTN or RYR1, large genes that are technically difficult to Sanger sequence. INTERPRETATION These data support NGS as a first-line tool for genetic evaluation of patients with a clinical phenotype suggestive of CMD, with muscle biopsy reserved as a second-tier investigation. Ann Neurol 2016;80:101-111.
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Affiliation(s)
- Gina L O'Grady
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Monkol Lek
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA.,Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA
| | - Shireen R Lamande
- Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, University of Melbourne, Parkville, Victoria, Australia
| | - Leigh Waddell
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Emily C Oates
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Jaya Punetha
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC
| | - Roula Ghaoui
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Sarah A Sandaradura
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Heather Best
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Simranpreet Kaur
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Mark Davis
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, QEII Medical Centre, Nedlands, Western Australia, Australia
| | - Nigel G Laing
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, QEII Medical Centre, Nedlands, Western Australia, Australia.,Centre for Medical Research, University of Western Australia, Perth, Western Australia, Australia.,Neurogenetic Unit, Harry Perkins Institute of Medical Research, Nedlands, Western Australia, Australia
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Institute of Child Health and Great Ormond Street Hospital for Children, London, United Kingdom
| | - Eric Hoffman
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC
| | - Daniel G MacArthur
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA.,Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA
| | - Nigel F Clarke
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Sandra Cooper
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Kathryn North
- Institute for Neuroscience and Muscle Research, Kids Research Institute, Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, Faculty of Medicine, University of Melbourne, Melbourne, Victoria, Australia
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105
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Gerin I, Ury B, Breloy I, Bouchet-Seraphin C, Bolsée J, Halbout M, Graff J, Vertommen D, Muccioli GG, Seta N, Cuisset JM, Dabaj I, Quijano-Roy S, Grahn A, Van Schaftingen E, Bommer GT. ISPD produces CDP-ribitol used by FKTN and FKRP to transfer ribitol phosphate onto α-dystroglycan. Nat Commun 2016; 7:11534. [PMID: 27194101 PMCID: PMC4873967 DOI: 10.1038/ncomms11534] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 04/06/2016] [Indexed: 01/27/2023] Open
Abstract
Mutations in genes required for the glycosylation of α-dystroglycan lead to muscle and brain diseases known as dystroglycanopathies. However, the precise structure and biogenesis of the assembled glycan are not completely understood. Here we report that three enzymes mutated in dystroglycanopathies can collaborate to attach ribitol phosphate onto α-dystroglycan. Specifically, we demonstrate that isoprenoid synthase domain-containing protein (ISPD) synthesizes CDP-ribitol, present in muscle, and that both recombinant fukutin (FKTN) and fukutin-related protein (FKRP) can transfer a ribitol phosphate group from CDP-ribitol to α-dystroglycan. We also show that ISPD and FKTN are essential for the incorporation of ribitol into α-dystroglycan in HEK293 cells. Glycosylation of α-dystroglycan in fibroblasts from patients with hypomorphic ISPD mutations is reduced. We observe that in some cases glycosylation can be partially restored by addition of ribitol to the culture medium, suggesting that dietary supplementation with ribitol should be evaluated as a therapy for patients with ISPD mutations.
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Affiliation(s)
- Isabelle Gerin
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Benoît Ury
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Isabelle Breloy
- Institute for Biochemistry II, Medical Faculty, University of Cologne, D-50931 Cologne, Germany
| | - Céline Bouchet-Seraphin
- AP-HP, Hôpital Bichat-Claude Bernard, Laboratoire de Biochimie Métabolique et Cellulaire, F-75018 Paris, France
| | - Jennifer Bolsée
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Mathias Halbout
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Julie Graff
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Didier Vertommen
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Giulio G Muccioli
- Louvain Drug Research Institute, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Nathalie Seta
- AP-HP, Hôpital Bichat-Claude Bernard, Laboratoire de Biochimie Métabolique et Cellulaire, F-75018 Paris, France
| | - Jean-Marie Cuisset
- Hôpital Roger-Salengro, Service de neuropédiatrie, Centre de Référence des Maladies Neuromusculaires, CHRU, F-59000 Lille, France
| | - Ivana Dabaj
- AP-HP, Hôpital R Poincaré, Service de pédiatrie, F-92380 Garches, France
| | - Susana Quijano-Roy
- AP-HP, Hôpital R Poincaré, Service de pédiatrie, F-92380 Garches, France.,Centre de Référence des Maladies Neuromusculaires, F-92380 Garches, France.,Université de Versailles-St Quentin, U1179 UVSQ - INSERM, F-78180 Montigny, France
| | - Ammi Grahn
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Emile Van Schaftingen
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
| | - Guido T Bommer
- WELBIO and de Duve Institute, Biological Chemistry, Université Catholique de Louvain, B-1200 Brussels, Belgium
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106
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Global serum glycoform profiling for the investigation of dystroglycanopathies & Congenital Disorders of Glycosylation. Mol Genet Metab Rep 2016; 7:55-62. [PMID: 27134828 PMCID: PMC4834675 DOI: 10.1016/j.ymgmr.2016.03.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 03/10/2016] [Indexed: 12/11/2022] Open
Abstract
The Congenital Disorders of Glycosylation (CDG) are an expanding group of genetic disorders which encompass a spectrum of glycosylation defects of protein and lipids, including N- & O-linked defects and among the latter are the muscular dystroglycanopathies (MD). Initial screening of CDG is usually based on the investigation of the glycoproteins transferrin, and/or apolipoprotein CIII. These biomarkers do not always detect complex or subtle defects present in older patients, therefore there is a need to investigate additional glycoproteins in some cases. We describe a sensitive 2D-Differential Gel Electrophoresis (DIGE) method that provides a global analysis of the serum glycoproteome. Patient samples from PMM2-CDG (n = 5), CDG-II (n = 7), MD and known complex N- & O-linked glycosylation defects (n = 3) were analysed by 2D DIGE. Using this technique we demonstrated characteristic changes in mass and charge in PMM2-CDG and in charge in CDG-II for α1-antitrypsin, α1-antichymotrypsin, α2-HS-glycoprotein, ceruloplasmin, and α1-acid glycoproteins 1&2. Analysis of the samples with known N- & O-linked defects identified a lower molecular weight glycoform of C1-esterase inhibitor that was not observed in the N-linked glycosylation disorders indicating the change is likely due to affected O-glycosylation. In addition, we could identify abnormal serum glycoproteins in LARGE and B3GALNT2-deficient muscular dystrophies. The results demonstrate that the glycoform pattern is varied for some CDG patients not all glycoproteins are consistently affected and analysis of more than one protein in complex cases is warranted. 2D DIGE is an ideal method to investigate the global glycoproteome and is a potentially powerful tool and secondary test for aiding the complex diagnosis and sub classification of CDG. The technique has further potential in monitoring patients for future treatment strategies. In an era of shifting emphasis from gel- to mass-spectral based proteomics techniques, we demonstrate that 2D-DIGE remains a powerful method for studying global changes in post-translational modifications of proteins.
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107
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DeRossi C, Vacaru A, Rafiq R, Cinaroglu A, Imrie D, Nayar S, Baryshnikova A, Milev MP, Stanga D, Kadakia D, Gao N, Chu J, Freeze HH, Lehrman MA, Sacher M, Sadler KC. trappc11 is required for protein glycosylation in zebrafish and humans. Mol Biol Cell 2016; 27:1220-34. [PMID: 26912795 PMCID: PMC4831877 DOI: 10.1091/mbc.e15-08-0557] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 02/12/2016] [Accepted: 02/19/2016] [Indexed: 12/23/2022] Open
Abstract
Activation of the unfolded protein response (UPR) can be either adaptive or pathological. We term the pathological UPR that causes fatty liver disease a "stressed UPR." Here we investigate the mechanism of stressed UPR activation in zebrafish bearing a mutation in thetrappc11gene, which encodes a component of the transport protein particle (TRAPP) complex.trappc11mutants are characterized by secretory pathway defects, reflecting disruption of the TRAPP complex. In addition, we uncover a defect in protein glycosylation intrappc11mutants that is associated with reduced levels of lipid-linked oligosaccharides (LLOs) and compensatory up-regulation of genes in the terpenoid biosynthetic pathway that produces the LLO anchor dolichol. Treating wild-type larvae with terpenoid or LLO synthesis inhibitors phenocopies the stressed UPR seen intrappc11mutants and is synthetically lethal withtrappc11mutation. We propose that reduced LLO level causing hypoglycosylation is a mechanism of stressed UPR induction intrappc11mutants. Of importance, in human cells, depletion of TRAPPC11, but not other TRAPP components, causes protein hypoglycosylation, and lipid droplets accumulate in fibroblasts from patients with theTRAPPC11mutation. These data point to a previously unanticipated and conserved role for TRAPPC11 in LLO biosynthesis and protein glycosylation in addition to its established function in vesicle trafficking.
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Affiliation(s)
- Charles DeRossi
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ana Vacaru
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ruhina Rafiq
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ayca Cinaroglu
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Dru Imrie
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Shikha Nayar
- Department of Pediatrics and Mindich Institute for Child Health, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Anastasia Baryshnikova
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544
| | - Miroslav P Milev
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Daniela Stanga
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| | - Dhara Kadakia
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Ningguo Gao
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jaime Chu
- Department of Pediatrics and Mindich Institute for Child Health, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Hudson H Freeze
- Sanford Children's Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Mark A Lehrman
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, QC H4B 1R6, Canada Department of Anatomy and Cell Biology, McGill University, Montreal, QC H3A 0C7, Canada
| | - Kirsten C Sadler
- Department of Medicine, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
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108
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Abstract
The dystrophin complex stabilizes the plasma membrane of striated muscle cells. Loss of function mutations in the genes encoding dystrophin, or the associated proteins, trigger instability of the plasma membrane, and myofiber loss. Mutations in dystrophin have been extensively cataloged, providing remarkable structure-function correlation between predicted protein structure and clinical outcomes. These data have highlighted dystrophin regions necessary for in vivo function and fueled the design of viral vectors and now, exon skipping approaches for use in dystrophin restoration therapies. However, dystrophin restoration is likely more complex, owing to the role of the dystrophin complex as a broad cytoskeletal integrator. This review will focus on dystrophin restoration, with emphasis on the regions of dystrophin essential for interacting with its associated proteins and discuss the structural implications of these approaches.
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Affiliation(s)
- Quan Q Gao
- Committee on Development, Regeneration and Stem Cell Biology, The University of Chicago, Chicago, Illinois, USA
| | - Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University, Chicago, Chicago, Illinois, USA
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109
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Thompson R, Straub V. Limb-girdle muscular dystrophies - international collaborations for translational research. Nat Rev Neurol 2016; 12:294-309. [PMID: 27033376 DOI: 10.1038/nrneurol.2016.35] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The limb-girdle muscular dystrophies (LGMDs) are a diverse group of genetic neuromuscular conditions that usually manifest in the proximal muscles of the hip and shoulder girdles. Since the identification of the first gene associated with the phenotype in 1994, an extensive body of research has identified the genetic defects responsible for over 30 LGMD subtypes, revealed an increasingly varied phenotypic spectrum, and exposed the need to move towards a systems-based understanding of the molecular pathways affected. New sequencing technologies, including whole-exome and whole-genome sequencing, are continuing to expand the range of genes and phenotypes associated with the LGMDs, and new computational approaches are helping clinicians to adapt to this new genomic medicine paradigm. However, 60 years on from the first description of LGMD, no curative therapies exist, and systematic exploration of the natural history is still lacking. To enable rapid translation of basic research to the clinic, well-phenotyped and genetically characterized patient cohorts are a necessity, and appropriate outcome measures and biomarkers must be developed through natural history studies. Here, we review the international collaborations that are addressing these translational research issues, and the lessons learned from large-scale LGMD sequencing programmes.
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Affiliation(s)
- Rachel Thompson
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK
| | - Volker Straub
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK
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110
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A New Mouse Model of Limb-Girdle Muscular Dystrophy Type 2I Homozygous for the Common L276I Mutation Mimicking the Mild Phenotype in Humans. J Neuropathol Exp Neurol 2016; 74:1137-46. [PMID: 26574668 DOI: 10.1097/nen.0000000000000260] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Limb-girdle muscular dystrophy type 2I (LGMD2I) is caused by mutations in the Fukutin-related protein (FKRP) gene, leading to inadequate glycosylation of α-dystroglycan, an important protein linking the extracellular matrix to the cytoskeleton. We created a mouse model of the common FKRP L276I mutation and a hemizygous FKRP L276I knockout model. We studied histopathology and protein expression in the models at different ages and found that homozygous FKRP L276I mice developed a mild progressive myopathy with increased muscle regeneration and fibrosis starting from 1 year of age. This was likely caused by progressive loss of α-dystroglycan-specific glycosylation, which was decreased by 78% at 20 months. The homozygous FKRP knockout was embryonic lethal, but the hemizygous L276I model resembled the homozygous FKRP L276I model at comparable ages. These models emphasize the importance of FKRP in maintaining proper glycosylation of α-dystroglycan. The mild progression in the homozygous FKRP L276I model resembles that in patients with LGMD2I who are homozygous for the L276I mutation. This animal model could, therefore, be relevant for understanding the pathophysiology of and developing a treatment strategy for the human disorder.
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111
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Where do we stand in trial readiness for autosomal recessive limb girdle muscular dystrophies? Neuromuscul Disord 2015; 26:111-25. [PMID: 26810373 DOI: 10.1016/j.nmd.2015.11.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 11/27/2015] [Accepted: 11/29/2015] [Indexed: 12/20/2022]
Abstract
Autosomal recessive limb girdle muscular dystrophies (LGMD2) are a group of genetically heterogeneous diseases that are typically characterised by progressive weakness and wasting of the shoulder and pelvic girdle muscles. Many of the more than 20 different conditions show overlapping clinical features with other forms of muscular dystrophy, congenital, myofibrillar or even distal myopathies and also with acquired muscle diseases. Although individually extremely rare, all types of LGMD2 together form an important differential diagnostic group among neuromuscular diseases. Despite improved diagnostics and pathomechanistic insight, a curative therapy is currently lacking for any of these diseases. Medical care consists of the symptomatic treatment of complications, aiming to improve life expectancy and quality of life. Besides well characterised pre-clinical tools like animal models and cell culture assays, the determinants of successful drug development programmes for rare diseases include a good understanding of the phenotype and natural history of the disease, the existence of clinically relevant outcome measures, guidance on care standards, up to date patient registries, and, ideally, biomarkers that can help assess disease severity or drug response. Strong patient organisations driving research and successful partnerships between academia, advocacy, industry and regulatory authorities can also help accelerate the elaboration of clinical trials. All these determinants constitute aspects of translational research efforts and influence patient access to therapies. Here we review the current status of determinants of successful drug development programmes for LGMD2, and the challenges of translating promising therapeutic strategies into effective and accessible treatments for patients.
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112
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Endo Y, Dong M, Noguchi S, Ogawa M, Hayashi YK, Kuru S, Sugiyama K, Nagai S, Ozasa S, Nonaka I, Nishino I. Milder forms of muscular dystrophy associated with POMGNT2 mutations. NEUROLOGY-GENETICS 2015; 1:e33. [PMID: 27066570 PMCID: PMC4811383 DOI: 10.1212/nxg.0000000000000033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 09/24/2015] [Indexed: 12/15/2022]
Abstract
Objective: To determine the genetic variants in patients with dystroglycanopathy (DGP) and assess the pathogenicity of these variants. Methods: A total of 20 patients with DGP were identified by immunohistochemistry or Western blot analysis. Whole-exome sequencing (WES) was performed using patient samples. The pathogenicity of the variants identified was evaluated on the basis of the phenotypic recovery in a knockout (KO) haploid human cell line by transfection with mutated POMGNT2 cDNA and on the basis of the in vitro enzymatic activity of mutated proteins. Results: WES identified homozygous and compound heterozygous missense variants in POMGNT2 in 3 patients with the milder limb-girdle muscular dystrophy (LGMD) and intellectual disability without brain malformation. The 2 identified variants were located in the putative glycosyltransferase domain of POMGNT2, which affected its enzymatic activity. Mutated POMGNT2 cDNAs failed to rescue the phenotype of POMGNT2-KO cells. Conclusions: Novel variants in POMGNT2 are associated with milder forms of LGMD. The findings of this study expand the clinical and pathologic spectrum of DGP associated with POMGNT2 variants from the severest Walker-Warburg syndrome to the mildest LGMD phenotypes. The simple method to verify pathogenesis of variants may allow researchers to evaluate any variants present in all of the known causative genes and the variants in novel candidate genes to detect DGPs, particularly without using patients' specimens.
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Affiliation(s)
- Yukari Endo
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Mingrui Dong
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Satoru Noguchi
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Megumu Ogawa
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Yukiko K Hayashi
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Satoshi Kuru
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Kenji Sugiyama
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Shigehiro Nagai
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Shiro Ozasa
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Ikuya Nonaka
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research (Y.E., M.D., S. Noguchi, M.O., Y.K.H., I. Nonaka, I. Nishino), National Institute of Neuroscience; and Department of Genome Medicine Development (Y.E., S. Noguchi, I. Nishino), Medical Genome Center, NCNP, Tokyo, Japan; Department of Neurology (M.D.), China-Japan Friendship Hospital, Beijing, China; Department of Pathophysiology (Y.K.H.), Tokyo Medical University; National Hospital Organization Suzuka National Hospital (S.K.), Mie, Japan; Department of Pediatrics (K.S.), Local Independent Administrative Institution, Mie Prefectural General Medical Center; Department of Child Neurology (S. Nagai), Shikoku Medical Center for Children and Adults, Kagawa, Japan; and Department of Pediatrics (S.O.), Kumamoto University, Kumamoto, Japan
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Human ISPD Is a Cytidyltransferase Required for Dystroglycan O-Mannosylation. ACTA ACUST UNITED AC 2015; 22:1643-52. [DOI: 10.1016/j.chembiol.2015.10.014] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/24/2015] [Accepted: 10/13/2015] [Indexed: 01/03/2023]
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114
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Krag TO, Vissing J. A New Mouse Model of Limb-Girdle Muscular Dystrophy Type 2I Homozygous for the Common L276I Mutation Mimicking the Mild Phenotype in Humans. J Neuropathol Exp Neurol 2015. [DOI: 10.1093/jnen/74.12.1137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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115
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Small molecules enhance functional O-mannosylation of Alpha-dystroglycan. Bioorg Med Chem 2015; 23:7661-70. [PMID: 26652968 DOI: 10.1016/j.bmc.2015.11.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/30/2015] [Accepted: 11/12/2015] [Indexed: 12/23/2022]
Abstract
Alpha-dystroglycan (α-DG), a highly glycosylated receptor for extracellular matrix proteins, plays a critical role in many biological processes. Hypoglycosylation of α-DG results in various types of muscular dystrophies and is also highly associated with progression of majority of cancers. Currently, there are no effective treatments for those devastating diseases. Enhancing functional O-mannosyl glycans (FOG) of α-DG on the cell surfaces is a potential approach to address this unmet challenge. Based on the hypothesis that the cells can up-regulate FOG of α-DG in response to certain chemical stimuli, we developed a cell-based high-throughput screening (HTS) platform for searching chemical enhancers of FOG of α-DG from a large chemical library with 364,168 compounds. Sequential validation of the hits from a primary screening campaign and chemical works led to identification of a cluster of compounds that positively modulate FOG of α-DG on various cell surfaces including patient-derived myoblasts. These compounds enhance FOG of α-DG by almost ten folds, which provide us powerful tools for O-mannosylation studies and potential starting points for the development of drug to treat dystroglycanopathy.
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116
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Ryckebüsch L. [Potential of the zebrafish model to study congenital muscular dystrophies]. Med Sci (Paris) 2015; 31:912-9. [PMID: 26481031 DOI: 10.1051/medsci/20153110018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In order to better understand the complexity of congenital muscular dystrophies (CMD) and develop new strategies to cure them, it is important to establish new disease models. Due to its numerous helpful attributes, the zebrafish has recently become a very powerful animal model for the study of CMD. For some CMD, this vertebrate model is phenotypically closer to human pathology than the murine model. Over the last few years, researchers have developed innovative techniques to screen rapidly and on a large scale for muscle defects in zebrafish. Furthermore, new genome editing techniques in zebrafish make possible the identification of new disease models. In this review, the major attributes of zebrafish for CMD studies are discussed and the principal models of CMD in zebrafish are highlighted.
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Affiliation(s)
- Lucile Ryckebüsch
- Division of biological sciences, university of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0380, La Jolla, États-Unis
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117
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Booler HS, Williams JL, Hopkinson M, Brown SC. Degree of Cajal-Retzius Cell Mislocalization Correlates with the Severity of Structural Brain Defects in Mouse Models of Dystroglycanopathy. Brain Pathol 2015; 26:465-78. [PMID: 26306834 DOI: 10.1111/bpa.12306] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/23/2015] [Indexed: 12/19/2022] Open
Abstract
The secondary dystroglycanopathies are characterized by the hypoglycosylation of alpha dystroglycan, and are associated with mutations in at least 18 genes that act on the glycosylation of this cell surface receptor rather than the Dag1 gene itself. At the severe end of the disease spectrum, there are substantial structural brain defects, the most striking of which is often cobblestone lissencephaly. The aim of this study was to determine the gene-specific aspects of the dystroglycanopathy brain phenotype through a detailed investigation of the structural brain defects present at birth in three mouse models of dystroglycanopathy-the FKRP(KD) , which has an 80% reduction in Fkrp transcript levels; the Pomgnt1null , which carries a deletion of exons 7-16 of the Pomgnt1 gene; and the Large(myd) mouse, which carries a deletion of exons 5-7 of the Large gene. We show a rostrocaudal and mediolateral gradient in the severity of brain lesions in FKRP(KD) , and to a lesser extent Pomgnt1null mice. Furthermore, the mislocalization of Cajal-Retzius cells is correlated with the gradient of these lesions and the severity of the brain phenotype in these models. Overall these observations implicate gene-specific differences in the pathogenesis of brain lesions in this group of disorders.
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Affiliation(s)
- Helen S Booler
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Josie L Williams
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Mark Hopkinson
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Susan C Brown
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
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118
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Magri F, Colombo I, Del Bo R, Previtali S, Brusa R, Ciscato P, Scarlato M, Ronchi D, D'Angelo MG, Corti S, Moggio M, Bresolin N, Comi GP. ISPD mutations account for a small proportion of Italian Limb Girdle Muscular Dystrophy cases. BMC Neurol 2015; 15:172. [PMID: 26404900 PMCID: PMC4582941 DOI: 10.1186/s12883-015-0428-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 09/14/2015] [Indexed: 12/16/2022] Open
Abstract
Background Limb Girdle Muscular Dystrophy (LGMD), caused by defective α-dystroglycan (α-DG) glycosylation, was recently associated with mutations in Isoprenoid synthase domain-containing (ISPD) and GDP-mannose pyrophosphorylase B (GMPPB) genes. The frequency of ISPD and GMPPB gene mutations in the LGMD population is unknown. Methods We investigated the contributions of ISPD and GMPPB genes in a cohort of 174 Italian patients with LGMD, including 140 independent probands. Forty-one patients (39 probands) from this cohort had not been genetically diagnosed. The contributions of ISPD and GMPPB were estimated by sequential α-DG immunohistochemistry (IHC) and mutation screening in patients with documented α-DG defect, or by direct DNA sequencing of both genes when muscle tissue was unavailable. Results We performed α-DG IHC in 27/39 undiagnosed probands: 24 subjects had normal α-DG expression, two had a partial deficiency, and one exhibited a complete absence of signal. Direct sequencing of ISPD and GMPPB revealed two heterozygous ISPD mutations in the individual who lacked α-DG IHC signal: c.836-5 T > G (which led to the deletion of exon 6 and the production of an out-of-frame transcript) and c.676 T > C (p.Tyr226His). This patient presented with sural hypertrophy and tip-toed walking at 5 years, developed moderate proximal weakness, and was fully ambulant at 42 years. The remaining 12/39 probands did not exhibit pathogenic sequence variation in either gene. Conclusion ISPD mutations are a rare cause of LGMD in the Italian population, accounting for less than 1 % of the entire cohort studied (FKRP mutations represent 10 %), while GMPPB mutations are notably absent in this patient sample. These data suggest that the genetic heterogeneity of LGMD with and without α-DG defects is greater than previously realized. Electronic supplementary material The online version of this article (doi:10.1186/s12883-015-0428-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Francesca Magri
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | - Irene Colombo
- Neuromuscular and Rare Disease Unit, Department of Neuroscience, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, via F. Sforza 35, 20132, Milan, Italy.
| | - Roberto Del Bo
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | - Stefano Previtali
- Inspe, Division of Neuroscience, San Raffaele, Via Olgettina 60, Milan, Italy.
| | - Roberta Brusa
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | - Patrizia Ciscato
- Neuromuscular and Rare Disease Unit, Department of Neuroscience, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, via F. Sforza 35, 20132, Milan, Italy.
| | - Marina Scarlato
- Inspe, Division of Neuroscience, San Raffaele, Via Olgettina 60, Milan, Italy.
| | - Dario Ronchi
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | | | - Stefania Corti
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | - Maurizio Moggio
- Neuromuscular and Rare Disease Unit, Department of Neuroscience, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, via F. Sforza 35, 20132, Milan, Italy.
| | - Nereo Bresolin
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
| | - Giacomo Pietro Comi
- Dino Ferrari Centre, Department of Neurological Sciences, University of Milan, I.R.C.C.S. Foundation Cà Granda, Ospedale Maggiore Policlinico, via F. Sforza 35, 20122, Milan, Italy.
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119
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Jensen BS, Willer T, Saade DN, Cox MO, Mozaffar T, Scavina M, Stefans VA, Winder TL, Campbell KP, Moore SA, Mathews KD. GMPPB-Associated Dystroglycanopathy: Emerging Common Variants with Phenotype Correlation. Hum Mutat 2015; 36:1159-63. [PMID: 26310427 DOI: 10.1002/humu.22898] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/12/2015] [Indexed: 11/11/2022]
Abstract
Mutations in GDP-mannose pyrophosphorylase B (GMPPB), a catalyst for the formation of the sugar donor GDP-mannose, were recently identified as a cause of muscular dystrophy resulting from abnormal glycosylation of α-dystroglycan. In this series, we report nine unrelated individuals with GMPPB-associated dystroglycanopathy. The most mildly affected subject has normal strength at 25 years, whereas three severely affected children presented in infancy with intellectual disability and epilepsy. Muscle biopsies of all subjects are dystrophic with abnormal immunostaining for glycosylated α-dystroglycan. This cohort, together with previously published cases, allows preliminary genotype-phenotype correlations to be made for the emerging GMPPB common variants c.79G>C (p.D27H) and c.860G>A (p.R287Q). We observe that c.79G>C (p.D27H) is associated with a mild limb-girdle muscular dystrophy phenotype, whereas c.860G>A (p.R287Q) is associated with a relatively severe congenital muscular dystrophy typically involving brain development. Sixty-six percent of GMPPB families to date have one of these common variants.
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Affiliation(s)
- Braden S Jensen
- Departments of Pediatrics and Neurology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Tobias Willer
- Howard Hughes Medical Institute, Departments of Molecular Physiology and Biophysics, Neurology, and Internal Medicine, University of Iowa Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Dimah N Saade
- Departments of Pediatrics and Neurology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Mary O Cox
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Tahseen Mozaffar
- Departments of Neurology and Orthopaedic Surgery, University of California, Irvine, California
| | - Mena Scavina
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, Delaware
| | - Vikki A Stefans
- Departments of Pediatrics and Physical Medicine and Rehabilitation, University of Arkansas for Medical Sciences College of Medicine, Little Rock, Arkansas
| | - Thomas L Winder
- Invitae Corp, San Francisco, California.,Prevention Genetics, Marshfield, Wisconsin
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Departments of Molecular Physiology and Biophysics, Neurology, and Internal Medicine, University of Iowa Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Steven A Moore
- Department of Pathology, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Katherine D Mathews
- Departments of Pediatrics and Neurology, University of Iowa Carver College of Medicine, Iowa City, Iowa
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Murphy AP, Straub V. The Classification, Natural History and Treatment of the Limb Girdle Muscular Dystrophies. J Neuromuscul Dis 2015; 2:S7-S19. [PMID: 27858764 PMCID: PMC5271430 DOI: 10.3233/jnd-150105] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Over sixty years ago John Walton and Frederick Nattrass defined limb girdle muscular dystrophy (LGMD) as a separate entity from the X-linked dystrophinopathies such as Duchenne and Becker muscular dystrophies. LGMD is a highly heterogeneous group of very rare neuromuscular disorders whose common factor is their autosomal inheritance. Sixty years later, with the development of increasingly advanced molecular genetic investigations, a more precise classification and understanding of the pathogenesis is possible.To date, over 30 distinct subtypes of LGMD have been identified, most of them inherited in an autosomal recessive fashion. There are significant differences in the frequency of subtypes of LGMD between different ethnic populations, providing evidence of founder mutations. Clinically there is phenotypic heterogeneity between subtypes of LGMD with varying severity and age of onset of symptoms. The first natural history studies into subtypes of LGMD are in process, but large scale longitudinal data have been lacking due to the rare nature of these diseases. Following natural history data collection, the next challenge is to develop more effective, disease specific treatments. Current management is focussed on symptomatic and supportive treatments. Advances in the application of new omics technologies and the generation of large-scale biomedical data will help to better understand disease mechanisms in LGMD and should ultimately help to accelerate the development of novel and more effective therapeutic approaches.
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Affiliation(s)
| | - Volker Straub
- Correspondence to: Volker Straub, The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, The International Centre for Life, Newcastle University, Central Parkway, Newcastle Upon Tyne, United Kingdom. NE1 3BZ. Tel.: +44 1912 418652; Fax: +44 1912 418770;
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121
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Evangelista T, Hanna M, Lochmüller H. Congenital Myasthenic Syndromes with Predominant Limb Girdle Weakness. J Neuromuscul Dis 2015; 2:S21-S29. [PMID: 26870666 PMCID: PMC4746746 DOI: 10.3233/jnd-150098] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Congenital myasthenic syndromes are a heterogeneous group of genetically determined disorders characterized by impaired neuromuscular transmission. They usually present from birth to childhood and are characterised by exercise induced weakness and fatigability. Genotype-phenotype correlations are difficult. However, in some patients particular phenotypic aspects may point towards a specific genetic defect. The absence of ptosis and ophthalmoparesis in patients with limb-girdle weakness makes the diagnosis of a neuromuscular transmission defect particularly challenging (LG-CMS). This is illustrated by a well-documented case published by Walton in 1956. The diagnosis of LG-CMS is secured by demonstrating a neuromuscular transmission defect with single fibre EMG or repetitive nerve stimulation, in the absence of auto-antibodies. Ultimately, a genetic test is required to identify the underlying cause and assure counselling and optimization of treatment. LG-CMS are inherited in autosomal recessive traits, and are often associated with mutations in DOK7 and GFPT1, and less frequently with mutations in COLQ, ALG2, ALG14 and DPAGT. Genetic characterization of CMS is of the upmost importance when choosing the adequate treatment. Some of the currently used drugs can either ameliorate or aggravate the symptoms depending on the underlying genetic defect. The drug most frequently used for the treatment of CMS is pyridostigmine an acetylcholinesterase inhibitor. However, pyridostigmine is not effective or is even detrimental in DOK7- and COLQ-related LG-CMS, while beta-adrenergic agonists (ephedrine, salbutamol) show some sustained benefit. Standard clinical trials may be difficult, but standardized follow-up of patients and international collaboration may help to improve the standards of care of these conditions.
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Affiliation(s)
- Teresinha Evangelista
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, UK
| | - Mike Hanna
- UCL MRC Centre for Neuromuscular Disease, Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | - Hanns Lochmüller
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, UK
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Van Schaftingen E, Veiga-da-Cunha M, Linster CL. Enzyme complexity in intermediary metabolism. J Inherit Metab Dis 2015; 38:721-7. [PMID: 25700988 DOI: 10.1007/s10545-015-9821-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 01/30/2015] [Accepted: 02/03/2015] [Indexed: 10/24/2022]
Abstract
A good appraisal of the function of enzymes is essential for the understanding of inborn errors of metabolism. However, it is clear now that the 'one gene, one enzyme, one catalytic function' rule oversimplifies the actual situation. Genes often encode several related proteins, which may differ in their subcellular localisation, regulation or function. Furthermore, enzymes often show several catalytic activities. In some cases, this is because they are multifunctional, possessing two or more different active sites that catalyse different, physiologically related reactions. In enzymes with broad specificity or in multispecificity enzymes, a single type of catalytic site performs the same reaction on different physiological substrates at similar rates. Enzymes that act physiologically in only one reaction often show nonetheless substrate promiscuity: they act at low rates on compounds that resemble their physiological substrate(s), thus forming non-classical metabolites, which are in some cases eliminated by metabolite repair. In addition to their catalytic role, enzymes may have moonlighting functions, i.e. non-catalytic functions that are most often not related with their catalytic activity. Deficiency in such functions may participate in the phenotype of inborn errors of metabolism. Evolution has also made that some enzymes have lost their catalytic activity to become allosteric proteins.
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Affiliation(s)
- Emile Van Schaftingen
- Welbio and de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200, Brussels, Belgium,
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Restoration of Functional Glycosylation of α-Dystroglycan in FKRP Mutant Mice Is Associated with Muscle Regeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:2025-37. [DOI: 10.1016/j.ajpath.2015.03.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 03/19/2015] [Accepted: 03/23/2015] [Indexed: 11/19/2022]
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Belaya K, Rodríguez Cruz PM, Liu WW, Maxwell S, McGowan S, Farrugia ME, Petty R, Walls TJ, Sedghi M, Basiri K, Yue WW, Sarkozy A, Bertoli M, Pitt M, Kennett R, Schaefer A, Bushby K, Parton M, Lochmüller H, Palace J, Muntoni F, Beeson D. Mutations in GMPPB cause congenital myasthenic syndrome and bridge myasthenic disorders with dystroglycanopathies. Brain 2015; 138:2493-504. [PMID: 26133662 PMCID: PMC4547052 DOI: 10.1093/brain/awv185] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 05/04/2015] [Indexed: 01/10/2023] Open
Abstract
Congenital myasthenic syndromes are associated with impairments in neuromuscular transmission. Belaya et al. show that mutations of the glycosylation pathway enzyme GMPPB, which has previously been implicated in muscular dystrophy dystroglycanopathy, also cause a congenital myasthenic syndrome. This differential diagnosis is important to ensure that affected individuals receive appropriate medication. Congenital myasthenic syndromes are inherited disorders that arise from impaired signal transmission at the neuromuscular junction. Mutations in at least 20 genes are known to lead to the onset of these conditions. Four of these, ALG2, ALG14, DPAGT1 and GFPT1, are involved in glycosylation. Here we identify a fifth glycosylation gene, GMPPB, where mutations cause congenital myasthenic syndrome. First, we identified recessive mutations in seven cases from five kinships defined as congenital myasthenic syndrome using decrement of compound muscle action potentials on repetitive nerve stimulation on electromyography. The mutations were present through the length of the GMPPB, and segregation, in silico analysis, exon trapping, cell transfection followed by western blots and immunostaining were used to determine pathogenicity. GMPPB congenital myasthenic syndrome cases show clinical features characteristic of congenital myasthenic syndrome subtypes that are due to defective glycosylation, with variable weakness of proximal limb muscle groups while facial and eye muscles are largely spared. However, patients with GMPPB congenital myasthenic syndrome had more prominent myopathic features that were detectable on muscle biopsies, electromyography, muscle magnetic resonance imaging, and through elevated serum creatine kinase levels. Mutations in GMPPB have recently been reported to lead to the onset of muscular dystrophy dystroglycanopathy. Analysis of four additional GMPPB-associated muscular dystrophy dystroglycanopathy cases by electromyography found that a defective neuromuscular junction component is not always present. Thus, we find mutations in GMPPB can lead to a wide spectrum of clinical features where deficit in neuromuscular transmission is the major component in a subset of cases. Clinical recognition of GMPPB-associated congenital myasthenic syndrome may be complicated by the presence of myopathic features, but correct diagnosis is important because affected individuals can respond to appropriate treatments.
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Affiliation(s)
- Katsiaryna Belaya
- 1 Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Pedro M Rodríguez Cruz
- 1 Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK 2 Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Wei Wei Liu
- 1 Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Susan Maxwell
- 1 Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Simon McGowan
- 3 Computational Biology Research Group, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Maria E Farrugia
- 4 Department of Neurology, Institute of Neurological Sciences, Southern General Hospital, Glasgow, UK
| | - Richard Petty
- 4 Department of Neurology, Institute of Neurological Sciences, Southern General Hospital, Glasgow, UK
| | - Timothy J Walls
- 5 Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 4LP, UK
| | - Maryam Sedghi
- 6 Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Keivan Basiri
- 7 Neurology Department, Neuroscience Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Wyatt W Yue
- 8 Structural Genomics Consortium, University of Oxford, Oxford, OX3 7DQ, UK
| | - Anna Sarkozy
- 9 Institute of Genetic Medicine, John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK 10 MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | - Marta Bertoli
- 9 Institute of Genetic Medicine, John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
| | - Matthew Pitt
- 11 Department of Clinical Neurophysiology, Great Ormond Street Hospital for children NHS foundation trust, London WC1N 3JH
| | - Robin Kennett
- 2 Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Andrew Schaefer
- 5 Department of Neurology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 4LP, UK
| | - Kate Bushby
- 9 Institute of Genetic Medicine, John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
| | - Matt Parton
- 10 MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | - Hanns Lochmüller
- 9 Institute of Genetic Medicine, John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Newcastle University, Newcastle upon Tyne, NE1 3BZ, UK
| | - Jacqueline Palace
- 2 Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Francesco Muntoni
- 12 Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Diseases, UCL Institute of Child Health, London, WC1N 1EH, UK
| | - David Beeson
- 1 Neurosciences Group, Nuffield Department of Clinical Neurosciences, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
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Kang PB, Morrison L, Iannaccone ST, Graham RJ, Bönnemann CG, Rutkowski A, Hornyak J, Wang CH, North K, Oskoui M, Getchius TSD, Cox JA, Hagen EE, Gronseth G, Griggs RC. Evidence-based guideline summary: evaluation, diagnosis, and management of congenital muscular dystrophy: Report of the Guideline Development Subcommittee of the American Academy of Neurology and the Practice Issues Review Panel of the American Association of Neuromuscular & Electrodiagnostic Medicine. Neurology 2015; 84:1369-78. [PMID: 25825463 DOI: 10.1212/wnl.0000000000001416] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE To delineate optimal diagnostic and therapeutic approaches to congenital muscular dystrophy (CMD) through a systematic review and analysis of the currently available literature. METHODS Relevant, peer-reviewed research articles were identified using a literature search of the MEDLINE, EMBASE, and Scopus databases. Diagnostic and therapeutic data from these articles were extracted and analyzed in accordance with the American Academy of Neurology classification of evidence schemes for diagnostic, prognostic, and therapeutic studies. Recommendations were linked to the strength of the evidence, other related literature, and general principles of care. RESULTS The geographic and ethnic backgrounds, clinical features, brain imaging studies, muscle imaging studies, and muscle biopsies of children with suspected CMD help predict subtype-specific diagnoses. Genetic testing can confirm some subtype-specific diagnoses, but not all causative genes for CMD have been described. Seizures and respiratory complications occur in specific subtypes. There is insufficient evidence to determine the efficacy of various treatment interventions to optimize respiratory, orthopedic, and nutritional outcomes, and more data are needed regarding complications. RECOMMENDATIONS Multidisciplinary care by experienced teams is important for diagnosing and promoting the health of children with CMD. Accurate assessment of clinical presentations and genetic data will help in identifying the correct subtype-specific diagnosis in many cases. Multiorgan system complications occur frequently; surveillance and prompt interventions are likely to be beneficial for affected children. More research is needed to fill gaps in knowledge regarding this category of muscular dystrophies.
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Affiliation(s)
- Peter B Kang
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Leslie Morrison
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Susan T Iannaccone
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Robert J Graham
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Carsten G Bönnemann
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Anne Rutkowski
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Joseph Hornyak
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Ching H Wang
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Kathryn North
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Maryam Oskoui
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Thomas S D Getchius
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Julie A Cox
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Erin E Hagen
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Gary Gronseth
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
| | - Robert C Griggs
- From the Division of Pediatric Neurology (P.B.K.), University of Florida College of Medicine, Gainesville; Department of Neurology (P.B.K.), Boston Children's Hospital and Harvard Medical School, Boston, MA; Department of Neurology (L.M.), University of New Mexico, Albuquerque; Departments of Pediatrics and Neurology & Neurotherapeutics (S.T.I.), University of Texas Southwestern Medical Center, and Children's Medical Center, Dallas; Division of Critical Care Medicine (R.J.G.), Boston Children's Hospital, and Department of Anaesthesia, Harvard Medical School, Boston; Neuromuscular and Neurogenetic Disorders of Childhood Section (C.G.B.), Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Cure Congenital Muscular Dystrophy (Cure CMD) (A.R.), Olathe, KS; Department of Emergency Medicine (A.R.), Kaiser Permanente South Bay Medical Center, Harbor City, CA; Department of Physical Medicine & Rehabilitation (J.H.), University of Michigan, Ann Arbor; Departments of Neurology and Pediatrics (C.H.W.), School of Medicine, Stanford University, CA; Department of Neurology (C.H.W.), Driscoll Children's Hospital, Corpus Christi, TX; Murdoch Childrens Research Institute (K.N.), The Royal Children's Hospital, and University of Melbourne, Australia; Neurology & Neurosurgery (M.O.), McGill University, Montréal, Canada; Center for Health Policy (T.S.D.G., J.A.C., E.E.H.), American Academy of Neurology, Minneapolis, MN; Department of Neurology (G.G.), University of Kansas School of Medicine, Kansas City; and Department of Neurology (R.C.G.), University of Rochester Medical Center, NY
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Gorokhova S, Biancalana V, Lévy N, Laporte J, Bartoli M, Krahn M. Clinical massively parallel sequencing for the diagnosis of myopathies. Rev Neurol (Paris) 2015; 171:558-71. [PMID: 26022190 DOI: 10.1016/j.neurol.2015.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 01/28/2015] [Accepted: 02/04/2015] [Indexed: 02/07/2023]
Abstract
Massively parallel sequencing, otherwise known as high-throughput or next-generation sequencing, is rapidly gaining wide use in clinical practice due to possibility of simultaneous exploration of multiple genomic regions. More than 300 genes have been implicated in neuromuscular disorders, meaning that many genes need to be considered in a differential diagnosis for a patient affected with myopathy. By providing sequencing information for numerous genes at the same time, massively parallel sequencing greatly accelerates the diagnostic processes of myopathies compared to the classical "gene-after-gene" approach by Sanger sequencing. In this review, we describe multiple advantages of this powerful sequencing method for applications in myopathy diagnosis. We also outline recent studies that used this approach to discover new myopathy-causing genes and to diagnose cohorts of patients with muscular disorders. Finally, we highlight the key aspects and limitations of massively parallel sequencing that a neurologist considering this test needs to know in order to interpret the results of the test and to deal with other issues concerning the test.
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Affiliation(s)
- S Gorokhova
- Aix Marseille Université, INSERM, GMGF, UMR_S 910, Faculté de Médecine, secteur Timone, 27, boulevard Jean-Moulin, 13385 Marseille cedex, France
| | - V Biancalana
- Laboratoire Diagnostic Génétique, Nouvel Hôpital Civil, 1, place de l'Hôpital, BP 426, 67091 Strasbourg cedex, France; Department of Translational Medicine and Neurogenetics, I.G.B.M.C., INSERM U964, CNRS UMR7104, Strasbourg University, 1, rue Laurent-Fries, 67404 Illkirch, France
| | - N Lévy
- Aix Marseille Université, INSERM, GMGF, UMR_S 910, Faculté de Médecine, secteur Timone, 27, boulevard Jean-Moulin, 13385 Marseille cedex, France; AP-HM, Département de Génétique Médicale, Hôpital Timone Enfants, 264, rue Saint-Pierre, 13385 Marseille cedex 05, France
| | - J Laporte
- Department of Translational Medicine and Neurogenetics, I.G.B.M.C., INSERM U964, CNRS UMR7104, Strasbourg University, 1, rue Laurent-Fries, 67404 Illkirch, France
| | - M Bartoli
- Aix Marseille Université, INSERM, GMGF, UMR_S 910, Faculté de Médecine, secteur Timone, 27, boulevard Jean-Moulin, 13385 Marseille cedex, France; AP-HM, Département de Génétique Médicale, Hôpital Timone Enfants, 264, rue Saint-Pierre, 13385 Marseille cedex 05, France
| | - M Krahn
- Aix Marseille Université, INSERM, GMGF, UMR_S 910, Faculté de Médecine, secteur Timone, 27, boulevard Jean-Moulin, 13385 Marseille cedex, France; AP-HM, Département de Génétique Médicale, Hôpital Timone Enfants, 264, rue Saint-Pierre, 13385 Marseille cedex 05, France.
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127
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Yoshida-Moriguchi T, Campbell KP. Matriglycan: a novel polysaccharide that links dystroglycan to the basement membrane. Glycobiology 2015; 25:702-13. [PMID: 25882296 PMCID: PMC4453867 DOI: 10.1093/glycob/cwv021] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 04/08/2015] [Indexed: 01/01/2023] Open
Abstract
Associations between cells and the basement membrane are critical for a variety of biological events including cell proliferation, cell migration, cell differentiation and the maintenance of tissue integrity. Dystroglycan is a highly glycosylated basement membrane receptor, and is involved in physiological processes that maintain integrity of the skeletal muscle, as well as development and function of the central nervous system. Aberrant O-glycosylation of the α subunit of this protein, and a concomitant loss of dystroglycan's ability to function as a receptor for extracellular matrix (ECM) ligands that bear laminin globular (LG) domains, occurs in several congenital/limb-girdle muscular dystrophies (also referred to as dystroglycanopathies). Recent genetic studies revealed that mutations in DAG1 (which encodes dystroglycan) and at least 17 other genes disrupt the ECM receptor function of dystroglycan and cause disease. Here, we summarize recent advances in our understanding of the enzymatic functions of two of these disease genes: the like-glycosyltransferase (LARGE) and protein O-mannose kinase (POMK, previously referred to as SGK196). In addition, we discuss the structure of the glycan that directly binds the ECM ligands and the mechanisms by which this functional motif is linked to dystroglycan. In light of the fact that dystroglycan functions as a matrix receptor and the polysaccharide synthesized by LARGE is the binding motif for matrix proteins, we propose to name this novel polysaccharide structure matriglycan.
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Affiliation(s)
- Takako Yoshida-Moriguchi
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, IA 52242-1101, USA
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, 4283 Carver Biomedical Research Building, 285 Newton Road, Iowa City, IA 52242-1101, USA
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128
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Bharucha-Goebel DX, Neil E, Donkervoort S, Dastgir J, Wiggs E, Winder TL, Moore SA, Iannaccone ST, Bönnemann CG. Intrafamilial variability in GMPPB-associated dystroglycanopathy: Broadening of the phenotype. Neurology 2015; 84:1495-7. [PMID: 25770200 DOI: 10.1212/wnl.0000000000001440] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 12/01/2014] [Indexed: 11/15/2022] Open
Affiliation(s)
- Diana X Bharucha-Goebel
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Erin Neil
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Sandra Donkervoort
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Jahannaz Dastgir
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Edythe Wiggs
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Thomas L Winder
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Steven A Moore
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Susan T Iannaccone
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA
| | - Carsten G Bönnemann
- From the National Institutes of Health (D.X.B.-G., S.D., E.A.W., C.G.B.), Bethesda, MD; Children's National Medical Center (D.X.B.-G.), Washington, DC; CS Mott Children's Hospital (E.N.), University of Michigan, Ann Arbor; Columbia University Medical Center (J.D.), New York, NY; Prevention Genetics (T.L.W.), Marshfield, WI; University of Iowa (S.A.M.), Iowa City; and University of Texas Southwestern Medical Center Dallas (S.T.I.), Dallas, TX. Dr. Winder is currently with Invitae Corp., San Francisco, CA.
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129
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Cabrera-Serrano M, Ghaoui R, Ravenscroft G, Johnsen RD, Davis MR, Corbett A, Reddel S, Sue CM, Liang C, Waddell LB, Kaur S, Lek M, North KN, MacArthur DG, Lamont PJ, Clarke NF, Laing NG. Expanding the phenotype of GMPPB mutations. ACTA ACUST UNITED AC 2015; 138:836-44. [PMID: 25681410 DOI: 10.1093/brain/awv013] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Dystroglycanopathies are a heterogeneous group of diseases with a broad phenotypic spectrum ranging from severe disorders with congenital muscle weakness, eye and brain structural abnormalities and intellectual delay to adult-onset limb-girdle muscular dystrophies without mental retardation. Most frequently the disease onset is congenital or during childhood. The exception is FKRP mutations, in which adult onset is a common presentation. Here we report eight patients from five non-consanguineous families where next generation sequencing identified mutations in the GMPPB gene. Six patients presented as an adult or adolescent-onset limb-girdle muscular dystrophy, one presented with isolated episodes of rhabdomyolysis, and one as a congenital muscular dystrophy. This report expands the phenotypic spectrum of GMPPB mutations to include limb-girdle muscular dystrophies with adult onset with or without intellectual disability, or isolated rhabdomyolysis.
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Affiliation(s)
- Macarena Cabrera-Serrano
- 1 Centre for Medical Research, University of Western Australia, Harry Perkins Institute of Medical Research, Perth, WA, Australia 2 Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
| | - Roula Ghaoui
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia 4 Discipline of Paediatrics and Child Health, University of Sydney, Sydney, NSW 2006, Australia 5 Department of Neurology, Royal North Shore Hospital, Sydney, Australia
| | - Gianina Ravenscroft
- 1 Centre for Medical Research, University of Western Australia, Harry Perkins Institute of Medical Research, Perth, WA, Australia
| | - Russell D Johnsen
- 6 Centre for Comparative Genomics, Murdoch University, Perth, Australia
| | - Mark R Davis
- 7 Department of Diagnostic Genomics, Pathwest Laboratory Medicine WA. Perth, WA, Australia
| | - Alastair Corbett
- 8 Department of Neurology, Concord Repatriation Hospital, and Sydney Medical School, Sydney, Australia
| | - Stephen Reddel
- 8 Department of Neurology, Concord Repatriation Hospital, and Sydney Medical School, Sydney, Australia
| | - Carolyn M Sue
- 5 Department of Neurology, Royal North Shore Hospital, Sydney, Australia
| | - Christina Liang
- 5 Department of Neurology, Royal North Shore Hospital, Sydney, Australia
| | - Leigh B Waddell
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia 4 Discipline of Paediatrics and Child Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Simranpreet Kaur
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia
| | - Monkol Lek
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia 4 Discipline of Paediatrics and Child Health, University of Sydney, Sydney, NSW 2006, Australia 9 Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA 10 Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Kathryn N North
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia 11 Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, Victoria, Australia 12 Department of Paediatrics, University of Melbourne, Victoria, Australia
| | - Daniel G MacArthur
- 9 Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA 10 Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Phillipa J Lamont
- 13 Neurogenetic Unit, Department of Neurology, Royal Perth Hospital, Perth, WA, Australia
| | - Nigel F Clarke
- 3 Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, Sydney, NSW 2145, Australia 4 Discipline of Paediatrics and Child Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Nigel G Laing
- 1 Centre for Medical Research, University of Western Australia, Harry Perkins Institute of Medical Research, Perth, WA, Australia
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130
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Ohtsuka Y, Kanagawa M, Yu CC, Ito C, Chiyo T, Kobayashi K, Okada T, Takeda S, Toda T. Fukutin is prerequisite to ameliorate muscular dystrophic phenotype by myofiber-selective LARGE expression. Sci Rep 2015; 5:8316. [PMID: 25661440 PMCID: PMC4321163 DOI: 10.1038/srep08316] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 01/13/2015] [Indexed: 12/22/2022] Open
Abstract
α-Dystroglycanopathy (α-DGP) is a group of muscular dystrophy characterized by abnormal glycosylation of α-dystroglycan (α-DG), including Fukuyama congenital muscular dystrophy (FCMD), muscle-eye-brain disease, Walker-Warburg syndrome, and congenital muscular dystrophy type 1D (MDC1D), etc. LARGE, the causative gene for MDC1D, encodes a glycosyltransferase to form [-3Xyl-α1,3GlcAβ1-] polymer in the terminal end of the post-phosphoryl moiety, which is essential for α-DG function. It has been proposed that LARGE possesses the great potential to rescue glycosylation defects in α-DGPs regardless of causative genes. However, the in vivo therapeutic benefit of using LARGE activity is controversial. To explore the conditions needed for successful LARGE gene therapy, here we used Large-deficient and fukutin-deficient mouse models for MDC1D and FCMD, respectively. Myofibre-selective LARGE expression via systemic adeno-associated viral gene transfer ameliorated dystrophic pathology of Large-deficient mice even when intervention occurred after disease manifestation. However, the same strategy failed to ameliorate the dystrophic phenotype of fukutin-conditional knockout mice. Furthermore, forced expression of Large in fukutin-deficient embryonic stem cells also failed to recover α-DG glycosylation, however coexpression with fukutin strongly enhanced α-DG glycosylation. Together, our data demonstrated that fukutin is required for LARGE-dependent rescue of α-DG glycosylation, and thus suggesting new directions for LARGE-utilizing therapy targeted to myofibres.
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Affiliation(s)
- Yoshihisa Ohtsuka
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Motoi Kanagawa
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Chih-Chieh Yu
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Chiyomi Ito
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Tomoko Chiyo
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, 187-8502, Japan
| | - Kazuhiro Kobayashi
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Takashi Okada
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, 187-8502, Japan
| | - Shin'ichi Takeda
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, 187-8502, Japan
| | - Tatsushi Toda
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
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131
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Abstract
Most proteins are modified by glycans, which can modulate the biological properties and functions of glycoproteins. The major glycans can be classified into N-glycans and O-glycans according to their glycan-peptide linkage. This review will provide an overview of the O-mannosyl glycans, one subtype of O-glycans. Originally, O-mannosyl glycan was only known to be present on a limited number of glycoproteins, especially α-dystroglycan (α-DG). However, once a clear relationship was established between O-mannosyl glycan and the pathological mechanisms of some congenital muscular dystrophies in humans, research on the biochemistry and pathology of O-mannosyl glycans has been expanding. Because α-DG glycosylation is defective in congenital muscular dystrophies, which also feature abnormal neuronal migration, these disorders are collectively called α-dystroglycanopathies. In this article, I will describe the structure, biosynthesis and pathology of O-mannosyl glycans.
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Affiliation(s)
- Tamao Endo
- Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo 173-0015, Japan
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132
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Neto OA, Tassy O, Biancalana V, Zanoteli E, Pourquié O, Laporte J. Integrative data mining highlights candidate genes for monogenic myopathies. PLoS One 2014; 9:e110888. [PMID: 25353622 PMCID: PMC4213015 DOI: 10.1371/journal.pone.0110888] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 09/18/2014] [Indexed: 11/25/2022] Open
Abstract
Inherited myopathies are a heterogeneous group of disabling disorders with still barely understood pathological mechanisms. Around 40% of afflicted patients remain without a molecular diagnosis after exclusion of known genes. The advent of high-throughput sequencing has opened avenues to the discovery of new implicated genes, but a working list of prioritized candidate genes is necessary to deal with the complexity of analyzing large-scale sequencing data. Here we used an integrative data mining strategy to analyze the genetic network linked to myopathies, derive specific signatures for inherited myopathy and related disorders, and identify and rank candidate genes for these groups. Training sets of genes were selected after literature review and used in Manteia, a public web-based data mining system, to extract disease group signatures in the form of enriched descriptor terms, which include functional annotation, human and mouse phenotypes, as well as biological pathways and protein interactions. These specific signatures were then used as an input to mine and rank candidate genes, followed by filtration against skeletal muscle expression and association with known diseases. Signatures and identified candidate genes highlight both potential common pathological mechanisms and allelic disease groups. Recent discoveries of gene associations to diseases, like B3GALNT2, GMPPB and B3GNT1 to congenital muscular dystrophies, were prioritized in the ranked lists, suggesting a posteriori validation of our approach and predictions. We show an example of how the ranked lists can be used to help analyze high-throughput sequencing data to identify candidate genes, and highlight the best candidate genes matching genomic regions linked to myopathies without known causative genes. This strategy can be automatized to generate fresh candidate gene lists, which help cope with database annotation updates as new knowledge is incorporated.
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Affiliation(s)
- Osorio Abath Neto
- Dept. of Translational Medicine and Neurogenetics, IGBMC, INSERM U964, CNRS UMR7104, University of Strasbourg, Collège de France, Illkirch, Strasbourg, France
- Departamento de Neurologia, Faculdade de Medicina de São Paulo (FMUSP), São Paulo, Brazil
| | - Olivier Tassy
- Dept. of Development & Stem Cells, IGBMC, INSERM U964, CNRS UMR7104, University of Strasbourg, Collège de France, Illkirch, Strasbourg, France
| | - Valérie Biancalana
- Dept. of Translational Medicine and Neurogenetics, IGBMC, INSERM U964, CNRS UMR7104, University of Strasbourg, Collège de France, Illkirch, Strasbourg, France
- Faculté de Médecine, Laboratoire de Diagnostic Génétique, Nouvel Hopital Civil, Strasbourg, France
| | - Edmar Zanoteli
- Departamento de Neurologia, Faculdade de Medicina de São Paulo (FMUSP), São Paulo, Brazil
| | - Olivier Pourquié
- Dept. of Development & Stem Cells, IGBMC, INSERM U964, CNRS UMR7104, University of Strasbourg, Collège de France, Illkirch, Strasbourg, France
| | - Jocelyn Laporte
- Dept. of Translational Medicine and Neurogenetics, IGBMC, INSERM U964, CNRS UMR7104, University of Strasbourg, Collège de France, Illkirch, Strasbourg, France
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133
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Wood AJ, Currie PD. Analysing regenerative potential in zebrafish models of congenital muscular dystrophy. Int J Biochem Cell Biol 2014; 56:30-7. [PMID: 25449259 DOI: 10.1016/j.biocel.2014.10.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 10/12/2014] [Accepted: 10/18/2014] [Indexed: 01/16/2023]
Abstract
The congenital muscular dystrophies (CMDs) are a clinically and genetically heterogeneous group of muscle disorders. Clinically hypotonia is present from birth, with progressive muscle weakness and wasting through development. For the most part, CMDs can mechanistically be attributed to failure of basement membrane protein laminin-α2 sufficiently binding with correctly glycosylated α-dystroglycan. The majority of CMDs therefore arise as the result of either a deficiency of laminin-α2 (MDC1A) or hypoglycosylation of α-dystroglycan (dystroglycanopathy). Here we consider whether by filling a regenerative medicine niche, the zebrafish model can address the present challenge of delivering novel therapeutic solutions for CMD. In the first instance the readiness and appropriateness of the zebrafish as a model organism for pioneering regenerative medicine therapies in CMD is analysed, in particular for MDC1A and the dystroglycanopathies. Despite the recent rapid progress made in gene editing technology, these approaches have yet to yield any novel zebrafish models of CMD. Currently the most genetically relevant zebrafish models to the field of CMD, have all been created by N-ethyl-N-nitrosourea (ENU) mutagenesis. Once genetically relevant models have been established the zebrafish has several important facets for investigating the mechanistic cause of CMD, including rapid ex vivo development, optical transparency up to the larval stages of development and relative ease in creating transgenic reporter lines. Together, these tools are well suited for use in live-imaging studies such as in vivo modelling of muscle fibre detachment. Secondly, the zebrafish's contribution to progress in effective treatment of CMD was analysed. Two approaches were identified in which zebrafish could potentially contribute to effective therapies. The first hinges on the augmentation of functional redundancy within the system, such as upregulating alternative laminin chains in the candyfloss fish, a model of MDC1A. Secondly high-throughput small molecule screens not only provide effective therapies, but also an alternative strategy for investigating CMD in zebrafish. In this instance insight into disease mechanism is derived in reverse. Zebrafish models are therefore clearly of critical importance in the advancement of regenerative medicine strategies in CMD. This article is part of a Directed Issue entitled: Regenerative Medicine: The challenge of translation.
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Affiliation(s)
- A J Wood
- Australian Regenerative Medicine Institute, Building 75, Level 1, Clayton Campus, Wellington Road, Melbourne, Victoroia 3181, Australia
| | - P D Currie
- Australian Regenerative Medicine Institute, Building 75, Level 1, Clayton Campus, Wellington Road, Melbourne, Victoroia 3181, Australia.
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134
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Sharma V, Ichikawa M, Freeze HH. Mannose metabolism: more than meets the eye. Biochem Biophys Res Commun 2014; 453:220-8. [PMID: 24931670 PMCID: PMC4252654 DOI: 10.1016/j.bbrc.2014.06.021] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 06/04/2014] [Indexed: 12/29/2022]
Abstract
Mannose is a simple sugar with a complex life. It is a welcome therapy for genetic and acquired human diseases, but it kills honeybees and blinds baby mice. It could cause diabetic complications. Mannose chemistry, metabolism, and metabolomics in cells, tissues and mammals can help explain these multiple systemic effects. Mannose has good, bad or ugly outcomes depending on its steady state levels and metabolic flux. This review describes the role of mannose at cellular level and its impact on organisms.
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Affiliation(s)
- Vandana Sharma
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
| | - Mie Ichikawa
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA
| | - Hudson H Freeze
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA
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135
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Kanagawa M, Lu Z, Ito C, Matsuda C, Miyake K, Toda T. Contribution of dysferlin deficiency to skeletal muscle pathology in asymptomatic and severe dystroglycanopathy models: generation of a new model for Fukuyama congenital muscular dystrophy. PLoS One 2014; 9:e106721. [PMID: 25198651 PMCID: PMC4157776 DOI: 10.1371/journal.pone.0106721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 08/01/2014] [Indexed: 11/18/2022] Open
Abstract
Defects in dystroglycan glycosylation are associated with a group of muscular dystrophies, termed dystroglycanopathies, that include Fukuyama congenital muscular dystrophy (FCMD). It is widely believed that abnormal glycosylation of dystroglycan leads to disease-causing membrane fragility. We previously generated knock-in mice carrying a founder retrotransposal insertion in fukutin, the gene responsible for FCMD, but these mice did not develop muscular dystrophy, which hindered exploring therapeutic strategies. We hypothesized that dysferlin functions may contribute to muscle cell viability in the knock-in mice; however, pathological interactions between glycosylation abnormalities and dysferlin defects remain unexplored. To investigate contributions of dysferlin deficiency to the pathology of dystroglycanopathy, we have crossed dysferlin-deficient dysferlin(sjl/sjl) mice to the fukutin-knock-in fukutin(Hp/-) and Large-deficient Largemyd/myd mice, which are phenotypically distinct models of dystroglycanopathy. The fukutin(Hp/-) mice do not show a dystrophic phenotype; however, (dysferlin(sjl/sjl): fukutin(Hp/-)) mice showed a deteriorated phenotype compared with (dysferlinsjl/sjl: fukutin(Hp/+)) mice. These data indicate that the absence of functional dysferlin in the asymptomatic fukutin(Hp/-) mice triggers disease manifestation and aggravates the dystrophic phenotype. A series of pathological analyses using double mutant mice for Large and dysferlin indicate that the protective effects of dysferlin appear diminished when the dystrophic pathology is severe and also may depend on the amount of dysferlin proteins. Together, our results show that dysferlin exerts protective effects on the fukutin(Hp/-) FCMD mouse model, and the (dysferlin(sjl/sjl): fukutin(Hp/-)) mice will be useful as a novel model for a recently proposed antisense oligonucleotide therapy for FCMD.
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Affiliation(s)
- Motoi Kanagawa
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Zhongpeng Lu
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Chiyomi Ito
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Chie Matsuda
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Katsuya Miyake
- Department of Histology and Cell Biology, School of Medicine, Kagawa University, Ikenobe, Miki, Kagawa, Japan
| | - Tatsushi Toda
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe, Japan
- * E-mail:
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136
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Townsend D. Finding the sweet spot: assembly and glycosylation of the dystrophin-associated glycoprotein complex. Anat Rec (Hoboken) 2014; 297:1694-705. [PMID: 25125182 PMCID: PMC4135523 DOI: 10.1002/ar.22974] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 03/27/2014] [Indexed: 01/12/2023]
Abstract
The dystrophin-associated glycoprotein complex (DGC) is a collection of glycoproteins that are essential for the normal function of striated muscle and many other tissues. Recent genetic studies have implicated the components of this complex in over a dozen forms of muscular dystrophy. Furthermore, disruption of the DGC has been implicated in many forms of acquired disease. This review aims to summarize the current state of knowledge regarding the processing and assembly of dystrophin-associated proteins with a focus primarily on the dystroglycan heterodimer and the sarcoglycan complex. These proteins form the transmembrane portion of the DGC and undergo a complex multi-step processing with proteolytic cleavage, differential assembly, and both N- and O-glycosylation. The enzymes responsible for this processing and a model describing the sequence and subcellular localization of these events are discussed.
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Affiliation(s)
- Dewayne Townsend
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, Minnesota
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137
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Clinical, pathologic, and mutational spectrum of dystroglycanopathy caused by LARGE mutations. J Neuropathol Exp Neurol 2014; 73:425-41. [PMID: 24709677 DOI: 10.1097/nen.0000000000000065] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Dystroglycanopathies are a subtype of congenital muscular dystrophy of varying severity that can affect the brain and eyes, ranging from Walker-Warburg syndrome with severe brain malformation to milder congenital muscular dystrophy presentations with affected or normal cognition and later onset. Mutations in dystroglycanopathy genes affect a specific glycoepitope on α-dystroglycan; of the 14 genes implicated to date, LARGE encodes the glycosyltransferase that adds the final xylose and glucuronic acid, allowing α-dystroglycan to bind ligands, including laminin 211 and neurexin. Only 11 patients with LARGE mutations have been reported. We report the clinical, neuroimaging, and genetic features of 4 additional patients. We confirm that gross deletions and rearrangements are important mutational mechanisms for LARGE. The brain abnormalities overshadowed the initially mild muscle phenotype in all 4 patients. We present the first comprehensive postnatal neuropathology of the brain, spinal cord, and eyes of a patient with a homozygous LARGE mutation at Cys443. In this patient, polymicrogyria was the predominant cortical malformation; densely festooned polymicrogyria were overlaid by a continuous agyric surface. In view of the severity of these abnormalities, Cys443 may be a functionally important residue in the LARGE protein, whereas the mutation p.Glu509Lys of Patient 1 in this study may confer a milder phenotype. Overall, these results expand the clinical and genetic spectrum of dystroglycanopathy.
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138
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Gupta VA, Beggs AH. Kelch proteins: emerging roles in skeletal muscle development and diseases. Skelet Muscle 2014; 4:11. [PMID: 24959344 PMCID: PMC4067060 DOI: 10.1186/2044-5040-4-11] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 05/06/2014] [Indexed: 12/11/2022] Open
Abstract
Our understanding of genes that cause skeletal muscle disease has increased tremendously over the past three decades. Advances in approaches to genetics and genomics have aided in the identification of new pathogenic mechanisms in rare genetic disorders and have opened up new avenues for therapeutic interventions by identification of new molecular pathways in muscle disease. Recent studies have identified mutations of several Kelch proteins in skeletal muscle disorders. The Kelch superfamily is one of the largest evolutionary conserved gene families. The 66 known family members all possess a Kelch-repeat containing domain and are implicated in diverse biological functions. In skeletal muscle development, several Kelch family members regulate the processes of proliferation and/or differentiation resulting in normal functioning of mature muscles. Importantly, many Kelch proteins function as substrate-specific adaptors for Cullin E3 ubiquitin ligase (Cul3), a core component of the ubiquitin-proteasome system to regulate the protein turnover. This review discusses the emerging roles of Kelch proteins in skeletal muscle function and disease.
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Affiliation(s)
- Vandana A Gupta
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA 02115, USA
| | - Alan H Beggs
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, 300 Longwood Ave., Boston, MA 02115, USA
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139
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Clinical, radiological, and genetic survey of patients with muscle-eye-brain disease caused by mutations in POMGNT1. Pediatr Neurol 2014; 50:491-7. [PMID: 24731844 DOI: 10.1016/j.pediatrneurol.2014.01.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/16/2013] [Accepted: 01/01/2014] [Indexed: 01/15/2023]
Abstract
BACKGROUND To evaluate clinical, genetic, and radiologic features of our patients with muscle-eye-brain disease. METHODS The data of patients who were diagnosed with muscle-eye-brain disease from a cohort of patients with congenital muscular dystrophy in the Division of Pediatric Neurology of Dokuz Eylül University School of Medicine and Gaziantep Children's Hospital between 2005 and 2013 were analyzed retrospectively. RESULTS From a cohort of 34 patients with congenital muscular dystrophy, 12 patients from 10 families were diagnosed with muscle-eye-brain disease. The mean age of the patients was 9 ± 5.5 years (2-19 years). Mean serum creatine kinase value was 2485.80 ± 1308.54 IU/L (700-4267 IU/L). All patients presented with muscular hypotonia at birth followed by varying degrees of spasticity and exaggerated deep tendon reflexes in later stages of life. Three patients were able to walk. The most common ophthalmologic and radiologic abnormalities were cataracts, retinal detachment, periventricular white matter abnormalities, ventriculomegaly, pontocerebellar hypoplasia, and multiple cerebellar cysts. All of the patients had mutations in the POMGNT1 gene. The most common mutation detected in 66% of patients was c.1814 G > A (p.R605H). Two novel mutations were identified. CONCLUSIONS We suggest that muscle-eye-brain disease is a relatively common muscular dystrophy in Turkey. It should be suspected in patients with muscular hypotonia, increased creatine kinase, and structural eye and brain abnormalities. The c.1814 G > A mutation in exon 21 of the POMGNT1 gene is apparently a common mutation in the Turkish population. Individuals with this mutation show classical features of muscle-eye-brain disease, but others may exhibit a milder phenotype and retain the ability to walk independently. Congenital muscular dystrophy patients from Turkey carrying the clinical and radiologic features of muscle-eye-brain disease should be evaluated for mutations in POMGNT1 gene.
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140
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A fourth case of POMT2-related limb girdle muscle dystrophy with mild reduction of α-dystroglycan glycosylation. Eur J Paediatr Neurol 2014; 18:404-8. [PMID: 24183756 DOI: 10.1016/j.ejpn.2013.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 10/17/2013] [Accepted: 10/17/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND POMT2 mutations have been identified in Walker-Warburg syndrome or muscle-eye-brain-like, but rarely in limb girdle muscular dystrophy (LGMD). RESULTS Two POMT2 mutations, one null and one missense, were found in a patient with LGMD and mild mental impairment, no brain or ocular involvement, minor histopathological features, and slight reduction of α-dystroglycan (α-DG) glycosylation and α-DG laminin binding. CONCLUSIONS Our case, the fourth LGMD POMT2-mutated reported to date, provides further evidence of correlation between level of α-DG glycosylation and phenotype severity.
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141
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NIGRO VINCENZO, SAVARESE MARCO. Genetic basis of limb-girdle muscular dystrophies: the 2014 update. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2014; 33:1-12. [PMID: 24843229 PMCID: PMC4021627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Limb-girdle muscular dystrophies (LGMD) are a highly heterogeneous group of muscle disorders, which first affect the voluntary muscles of the hip and shoulder areas. The definition is highly descriptive and less ambiguous by exclusion: non-Xlinked, non-FSH, non-myotonic, non-distal, nonsyndromic, and non-congenital. At present, the genetic classification is becoming too complex, since the acronym LGMD has also been used for a number of other myopathic disorders with overlapping phenotypes. Today, the list of genes to be screened is too large for the gene-by-gene approach and it is well suited for targeted next generation sequencing (NGS) panels that should include any gene that has been so far associated with a clinical picture of LGMD. The present review has the aim of recapitulating the genetic basis of LGMD ordering and of proposing a nomenclature for the orphan forms. This is useful given the pace of new discoveries. Thity-one loci have been identified so far, eight autosomal dominant and 23 autosomal recessive. The dominant forms (LGMD1) are: LGMD1A (myotilin), LGMD1B (lamin A/C), LGMD1C (caveolin 3), LGMD1D (DNAJB6), LGMD1E (desmin), LGMD1F (transportin 3), LGMD1G (HNRPDL), LGMD1H (chr. 3). The autosomal recessive forms (LGMD2) are: LGMD2A (calpain 3), LGMD2B (dysferlin), LGMD2C (γ sarcoglycan), LGMD2D (α sarcoglycan), LGMD2E (β sarcoglycan), LGMD2F (δ sarcoglycan), LGMD2G (telethonin), LGMD2H (TRIM32), LGMD2I (FKRP), LGMD2J (titin), LGMD2K (POMT1), LGMD2L (anoctamin 5), LGMD2M (fukutin), LGMD2N (POMT2), LGMD2O (POMTnG1), LGMD2P (dystroglycan), LGMD2Q (plectin), LGMD2R (desmin), LGMD2S (TRAPPC11), LGMD2T (GMPPB), LGMD2U (ISPD), LGMD2V (Glucosidase, alpha ), LGMD2W (PINCH2).
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Affiliation(s)
- VINCENZO NIGRO
- Address for correspondence: Vincenzo Nigro, via Luigi De Crecchio 7, 80138 Napoli, Italy; Telethon Institute of Genetics and Medicine (TIGEM), via Pietro Castellino 111, 80131 Napoli, Italy. - E-mail:
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142
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Raphael AR, Couthouis J, Sakamuri S, Siskind C, Vogel H, Day JW, Gitler AD. Congenital muscular dystrophy and generalized epilepsy caused by GMPPB mutations. Brain Res 2014; 1575:66-71. [PMID: 24780531 DOI: 10.1016/j.brainres.2014.04.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 04/04/2014] [Accepted: 04/06/2014] [Indexed: 12/30/2022]
Abstract
The alpha-dystroglycanopathies are genetically heterogeneous muscular dystrophies that result from hypoglycosylation of alpha-dystroglycan (α-DG). Alpha-dystroglycan is an essential link between the extracellular matrix and the muscle fiber sarcolemma, and proper glycosylation is critical for its ability to bind to ligands in the extracellular matrix. We sought to identify the genetic basis of alpha-dystroglycanopathy in a family wherein the affected individuals presented with congenital muscular dystrophy, brain abnormalities and generalized epilepsy. We performed whole exome sequencing and identified compound heterozygous GMPPB mutations in the affected children. GMPPB is an enzyme in the glycosylation pathway, and GMPPB mutations were recently linked to eight cases of alpha-dystroglycanopathy with a range of symptoms. We identified a novel mutation in GMPPB (p.I219T) as well as a previously published mutation (p.R287Q). Thus, our work further confirms a role for GMPPB defects in alpha-dystroglycanopathy, and suggests that glycosylation may play a role in the neuronal membrane channels or networks involved in the physiology of generalized epilepsy syndromes. This article is part of a Special Issue entitled RNA Metabolism 2013.
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Affiliation(s)
- Alya R Raphael
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Julien Couthouis
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sarada Sakamuri
- Department of Neurology, Stanford University School of Medicine, Stanford, CA, USA
| | - Carly Siskind
- Department of Neurology, Stanford University School of Medicine, Stanford, CA, USA; Neuroscience Center, Stanford Hospital and Clinics, Stanford, CA, USA
| | - Hannes Vogel
- Departments of Pathology and Pediatrics, Stanford University School of Medicine, Stanford, CA, USA
| | - John W Day
- Department of Neurology, Stanford University School of Medicine, Stanford, CA, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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Saito F, Kanagawa M, Ikeda M, Hagiwara H, Masaki T, Ohkuma H, Katanosaka Y, Shimizu T, Sonoo M, Toda T, Matsumura K. Overexpression of LARGE suppresses muscle regeneration via down-regulation of insulin-like growth factor 1 and aggravates muscular dystrophy in mice. Hum Mol Genet 2014; 23:4543-58. [PMID: 24722207 DOI: 10.1093/hmg/ddu168] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Several types of muscular dystrophy are caused by defective linkage between α-dystroglycan (α-DG) and laminin. Among these, dystroglycanopathy, including Fukuyama-type congenital muscular dystrophy (FCMD), results from abnormal glycosylation of α-DG. Recent studies have shown that like-acetylglucosaminyltransferase (LARGE) strongly enhances the laminin-binding activity of α-DG. Therefore, restoration of the α-DG-laminin linkage by LARGE is considered one of the most promising possible therapies for muscular dystrophy. In this study, we generated transgenic mice that overexpress LARGE (LARGE Tg) and crossed them with dy(2J) mice and fukutin conditional knockout mice, a model for laminin α2-deficient congenital muscular dystrophy (MDC1A) and FCMD, respectively. Remarkably, in both the strains, the transgenic overexpression of LARGE resulted in an aggravation of muscular dystrophy. Using morphometric analyses, we found that the deterioration of muscle pathology was caused by suppression of muscle regeneration. Overexpression of LARGE in C2C12 cells further demonstrated defects in myotube formation. Interestingly, a decreased expression of insulin-like growth factor 1 (IGF-1) was identified in both LARGE Tg mice and LARGE-overexpressing C2C12 myotubes. Supplementing the C2C12 cells with IGF-1 restored the defective myotube formation. Taken together, our findings indicate that the overexpression of LARGE aggravates muscular dystrophy by suppressing the muscle regeneration and this adverse effect is mediated via reduced expression of IGF-1.
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Affiliation(s)
- Fumiaki Saito
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan,
| | - Motoi Kanagawa
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Miki Ikeda
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Hiroki Hagiwara
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan, Department of Medical Science, Teikyo University of Science, Uenohara Campus, Uenohara-shi 409-0193, Japan
| | - Toshihiro Masaki
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan, Department of Medical Science, Teikyo University of Science, Senju Campus, Tokyo 120-0045, Japan
| | - Hidehiko Ohkuma
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Yuki Katanosaka
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan and
| | - Teruo Shimizu
- Department of Sport and Medical Science, Teikyo University Faculty of Medical Technology, Tokyo 173-8605, Japan
| | - Masahiro Sonoo
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Tatsushi Toda
- Division of Neurology/Molecular Brain Science, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Kiichiro Matsumura
- Department of Neurology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
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Wallace SE, Conta JH, Winder TL, Willer T, Eskuri JM, Haas R, Patterson K, Campbell KP, Moore SA, Gospe SM. A novel missense mutation in POMT1 modulates the severe congenital muscular dystrophy phenotype associated with POMT1 nonsense mutations. Neuromuscul Disord 2014; 24:312-20. [PMID: 24491487 PMCID: PMC3959257 DOI: 10.1016/j.nmd.2014.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 12/16/2013] [Accepted: 01/03/2014] [Indexed: 10/25/2022]
Abstract
Mutations in POMT1 lead to a group of neuromuscular conditions ranging in severity from Walker-Warburg syndrome to limb girdle muscular dystrophy. We report two male siblings, ages 19 and 14, and an unrelated 6-year old female with early onset muscular dystrophy and intellectual disability with minimal structural brain anomalies and no ocular abnormalities. Compound heterozygous mutations in POMT1 were identified including a previously reported nonsense mutation (c.2167dupG; p.Asp723Glyfs*8) associated with Walker-Warburg syndrome and a novel missense mutation in a highly conserved region of the protein O-mannosyltransferase 1 protein (c.1958C>T; p.Pro653Leu). This novel variant reduces the phenotypic severity compared to patients with homozygous c.2167dupG mutations or compound heterozygous patients with a c.2167dupG mutation and a wide range of other mutant POMT1 alleles.
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Affiliation(s)
- Stephanie E Wallace
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, United States; Seattle Children's Hospital, Seattle, WA, United States
| | - Jessie H Conta
- Department of Laboratories, Seattle Children's Hospital, Seattle, WA, United States
| | | | - Tobias Willer
- Howard Hughes Medical Institute and Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Jamie M Eskuri
- Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Richard Haas
- Department of Neurosciences University of California, San Diego, La Jolla, CA, United States; Department of Pediatrics, University of California, San Diego, La Jolla, CA, United States; Rady Children's Hospital San Diego, CA, United States
| | - Kathleen Patterson
- Department of Pathology, Seattle Children's Hospital, Seattle, WA, United States
| | - Kevin P Campbell
- Howard Hughes Medical Institute and Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States; Department of Neurology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States; Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Steven A Moore
- Department of Pathology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Sidney M Gospe
- Department of Neurology, University of Washington, Seattle, WA, United States; Department of Pediatrics, University of Washington, Seattle, WA, United States; Seattle Children's Hospital, Seattle, WA, United States.
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Bönnemann CG, Wang CH, Quijano-Roy S, Deconinck N, Bertini E, Ferreiro A, Muntoni F, Sewry C, Béroud C, Mathews KD, Moore SA, Bellini J, Rutkowski A, North KN. Diagnostic approach to the congenital muscular dystrophies. Neuromuscul Disord 2014; 24:289-311. [PMID: 24581957 PMCID: PMC5258110 DOI: 10.1016/j.nmd.2013.12.011] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/23/2013] [Accepted: 12/31/2013] [Indexed: 12/14/2022]
Abstract
Congenital muscular dystrophies (CMDs) are early onset disorders of muscle with histological features suggesting a dystrophic process. The congenital muscular dystrophies as a group encompass great clinical and genetic heterogeneity so that achieving an accurate genetic diagnosis has become increasingly challenging, even in the age of next generation sequencing. In this document we review the diagnostic features, differential diagnostic considerations and available diagnostic tools for the various CMD subtypes and provide a systematic guide to the use of these resources for achieving an accurate molecular diagnosis. An International Committee on the Standard of Care for Congenital Muscular Dystrophies composed of experts on various aspects relevant to the CMDs performed a review of the available literature as well as of the unpublished expertise represented by the members of the committee and their contacts. This process was refined by two rounds of online surveys and followed by a three-day meeting at which the conclusions were presented and further refined. The combined consensus summarized in this document allows the physician to recognize the presence of a CMD in a child with weakness based on history, clinical examination, muscle biopsy results, and imaging. It will be helpful in suspecting a specific CMD subtype in order to prioritize testing to arrive at a final genetic diagnosis.
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Affiliation(s)
- Carsten G Bönnemann
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States.
| | - Ching H Wang
- Driscoll Children's Hospital, Corpus Christi, TX, United States
| | - Susana Quijano-Roy
- Hôpital Raymond Poincaré, Garches, and UFR des sciences de la santé Simone Veil (UVSQ), France
| | - Nicolas Deconinck
- Hôpital Universitaire des Enfants Reine Fabiola, Brussels and Ghent University Hospital, Ghent, Belgium
| | | | - Ana Ferreiro
- UMR787 INSERM/UPMC and Reference Center for Neuromuscular Disorders, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Institute of Child Health, London, United Kingdom
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre, UCL Institute of Child Health, London, United Kingdom
| | - Christophe Béroud
- INSERM U827, Laboratoire de Génétique Moleculaire, Montpellier, France
| | | | | | - Jonathan Bellini
- Stanford University School of Medicine, Stanford, CA, United States
| | | | - Kathryn N North
- Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
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146
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Blaeser A, Sparks S, Brown SC, Campbell K, Lu Q. Third International Workshop for Glycosylation Defects in Muscular Dystrophies, 18-19 April 2013, Charlotte, USA. Brain Pathol 2014; 24:280-4. [PMID: 24397416 DOI: 10.1111/bpa.12118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 12/18/2013] [Indexed: 12/21/2022] Open
Affiliation(s)
- Anthony Blaeser
- McColl-Lockwood Laboratory for Muscular Dystrophy Research, Neuromuscular/ALS Center, Carolinas Medical Center, Carolinas Healthcare System, Charlotte, NC
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147
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von Renesse A, Petkova MV, Lützkendorf S, Heinemeyer J, Gill E, Hübner C, von Moers A, Stenzel W, Schuelke M. POMK mutation in a family with congenital muscular dystrophy with merosin deficiency, hypomyelination, mild hearing deficit and intellectual disability. J Med Genet 2014; 51:275-82. [PMID: 24556084 DOI: 10.1136/jmedgenet-2013-102236] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Congenital muscular dystrophies (CMD) with hypoglycosylation of α-dystroglycan are clinically and genetically heterogeneous disorders that are often associated with brain malformations and eye defects. Presently, 16 proteins are known whose dysfunction impedes glycosylation of α-dystroglycan and leads to secondary dystroglycanopathy. OBJECTIVE To identify the cause of CMD with secondary merosin deficiency, hypomyelination and intellectual disability in two siblings from a consanguineous family. METHODS Autozygosity mapping followed by whole exome sequencing and immunochemistry were used to discover and verify a new genetic defect in two siblings with CMD. RESULTS We identified a homozygous missense mutation (c.325C>T, p.Q109*) in protein O-mannosyl kinase (POMK) that encodes a glycosylation-specific kinase (SGK196) required for function of the dystroglycan complex. The protein was absent from skeletal muscle and skin fibroblasts of the patients. In patient muscle, β-dystroglycan was normally expressed at the sarcolemma, while α-dystroglycan failed to do so. Further, we detected co-localisation of POMK with desmin at the costameres in healthy muscle, and a substantial loss of desmin from the patient muscle. CONCLUSIONS Homozygous truncating mutations in POMK lead to CMD with secondary merosin deficiency, hypomyelination and intellectual disability. Loss of desmin suggests that failure of proper α-dystroglycan glycosylation impedes the binding to extracellular matrix proteins and also affects the cytoskeleton.
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Affiliation(s)
- Anja von Renesse
- Department of Neuropediatrics, Charité-Universitätsmedizin Berlin, Berlin, Germany
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148
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Czeschik JC, Hehr U, Hartmann B, Lüdecke HJ, Rosenbaum T, Schweiger B, Wieczorek D. 160 kb deletion in ISPD unmasking a recessive mutation in a patient with Walker–Warburg syndrome. Eur J Med Genet 2013; 56:689-94. [DOI: 10.1016/j.ejmg.2013.09.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 09/30/2013] [Indexed: 01/03/2023]
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149
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Yagi H, Nakagawa N, Saito T, Kiyonari H, Abe T, Toda T, Wu SW, Khoo KH, Oka S, Kato K. AGO61-dependent GlcNAc modification primes the formation of functional glycans on α-dystroglycan. Sci Rep 2013; 3:3288. [PMID: 24256719 PMCID: PMC3836086 DOI: 10.1038/srep03288] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/05/2013] [Indexed: 12/27/2022] Open
Abstract
Dystroglycanopathy is a major class of congenital muscular dystrophy that is caused by a deficiency of functional glycans on α-dystroglycan (α-DG) with laminin-binding activity. A product of a recently identified causative gene for dystroglycanopathy, AGO61, acted in vitro as a protein O-mannose β-1, 4-N-acetylglucosaminyltransferase, although it was not functionally characterized. Here we show the phenotypes of AGO61-knockout mice and demonstrate that AGO61 is indispensable for the formation of laminin-binding glycans of α-DG. AGO61-knockout mouse brain exhibited abnormal basal lamina formation and a neuronal migration defect due to a lack of laminin-binding glycans. Furthermore, our results indicate that functional α-DG glycosylation was primed by AGO61-dependent GlcNAc modifications of specific threonine-linked mannosyl moieties of α-DG. These findings provide a key missing link for understanding how the physiologically critical glycan motif is displayed on α-DG and provides new insights on the pathological mechanisms of dystroglycanopathy.
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Affiliation(s)
- Hirokazu Yagi
- 1] Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan [2]
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150
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Whitmore C, Fernandez-Fuente M, Booler H, Parr C, Kavishwar M, Ashraf A, Lacey E, Kim J, Terry R, Ackroyd MR, Wells KE, Muntoni F, Wells DJ, Brown SC. The transgenic expression of LARGE exacerbates the muscle phenotype of dystroglycanopathy mice. Hum Mol Genet 2013; 23:1842-55. [PMID: 24234655 DOI: 10.1093/hmg/ddt577] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mutations in fukutin-related protein (FKRP) underlie a group of muscular dystrophies associated with the hypoglycosylation of α-dystroglycan (α-DG), a proportion of which show central nervous system involvement. Our original FKRP knock-down mouse (FKRP(KD)) replicated many of the characteristics seen in patients at the severe end of the dystroglycanopathy spectrum but died perinatally precluding its full phenotyping and use in testing potential therapies. We have now overcome this by crossing FKRP(KD) mice with those expressing Cre recombinase under the Sox1 promoter. Owing to our original targeting strategy, this has resulted in the restoration of Fkrp levels in the central nervous system but not the muscle, thereby generating a new model (FKRP(MD)) which develops a progressive muscular dystrophy resembling what is observed in limb girdle muscular dystrophy. Like-acetylglucosaminyltransferase (LARGE) is a bifunctional glycosyltransferase previously shown to hyperglycosylate α-DG. To investigate the therapeutic potential of LARGE up-regulation, we have now crossed the FKRP(MD) line with one overexpressing LARGE and show that, contrary to expectation, this results in a worsening of the muscle pathology implying that any future strategies based upon LARGE up-regulation require careful management.
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Affiliation(s)
- Charlotte Whitmore
- Comparative Biomedical Sciences, Royal Veterinary College, University of London, London NW1 0TU, UK
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