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Zanotti S, Magri F, Poggetti F, Ripolone M, Velardo D, Fortunato F, Ciscato P, Moggio M, Corti S, Comi GP, Sciacco M. Immunofluorescence signal intensity measurements as a semi-quantitative tool to assess sarcoglycan complex expression in muscle biopsy. Eur J Histochem 2022; 66. [PMID: 36047345 PMCID: PMC9471914 DOI: 10.4081/ejh.2022.3418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Sarcoglycanopathies are highly heterogeneous in terms of disease progression, muscular weakness, loss of ambulation and cardiac/respiratory involvement. Their clinical severity usually correlates with the residual protein amount, which makes protein quantification extremely relevant. Sarcoglycanopathy diagnosis is genetic, but skeletal muscle analysis - by both immunohistochemistry and Western blot (WB) - is still mandatory to establish the correct diagnostic process. Unfortunately, however, WB analysis cannot be performed if the bioptic specimen is scarce. This study provides a sensitive tool for semi-quantification of residual amount of sarcoglycans in patients affected by sarcoglycanopathies, based on immunofluorescence staining on skeletal muscle sections, image acquisition and software elaboration. We applied this method to eleven sarcoglycanopathies, seven Becker muscular dystrophies, as pathological control group, and four age-matched controls. Fluorescence data showed a significantly reduced expression of the mutated sarcoglycan in all patients when compared to their respective age-matched healthy controls, and a variable reduction of the other sarcoglycans. The reduction is due to the effect of gene mutation and not to the increasing age of controls. Fluorescence normalized data analyzed in relation to the age of onset of the disease, showed a negative correlation of a-sarcoglycan fluorescence signal vs fibrosis in patients with an early age of onset and a negative correlation between d-sarcoglycan signal and fibrosis in both intermediate and late age of onset groups. The availability of a method that allows objective quantification of the sarcolemmal proteins, faster and less consuming than WB analysis and able to detect low residual sarcoglycan expression with great sensitivity, proves useful also in view of possible inferences on disease prognosis. The proposed method could be employed also to monitor the efficacy of therapeutic interventions and during clinical trials.
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Affiliation(s)
- Simona Zanotti
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesca Magri
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesca Poggetti
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Michela Ripolone
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Daniele Velardo
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesco Fortunato
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Patrizia Ciscato
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Maurizio Moggio
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Stefania Corti
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Giacomo Pietro Comi
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Monica Sciacco
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
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Carson L, Merrick D. Genotype-phenotype correlations in alpha-sarcoglycanopathy: a systematic review. Ir J Med Sci 2022; 191:2743-2750. [PMID: 35040091 DOI: 10.1007/s11845-021-02855-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 10/27/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Mutations in the alpha-sarcoglycan gene cause limb-girdle muscular dystrophy 2D, an autosomal recessive muscle wasting disorder primarily affecting the muscles of the shoulder and pelvic girdles. To date, no previous study has collated all known mutations in alpha-sarcoglycan and mapped these to the associated phenotypes. AIMS To examine for correlations between mutation locations, or mutation type, and the phenotype caused in all reported mutations in alpha-sarcoglycan. METHODS We present a systematic literature review examining correlations between mutation locations, or mutation type, and the phenotype caused in all reported cases of limb-girdle muscular dystrophy 2D. RESULTS From 134 unique genotypes collated, a strong prevalence of missense mutations (64% of all unique mutations) was found in this gene. Mutation hotspots were noted in exon three and the extracellular domain, with mutation densities varying significantly between both exons and protein domains (p ≤ 0.01). All compound heterozygous limb-girdle muscular dystrophy 2D patients with cardiac involvement contained at least one mutation in exon three, a novel finding. All non-sense mutations in alpha-sarcoglycan give a severe phenotype, as do genotypes involving a combination of exons four and five. This study confirms on a large, diverse cohort the extremely high prevalence of the c.229C > T mutation. CONCLUSIONS This study demonstrates the vast variation in disease severity seen between patients possessing the same mutation, highlighting the difficulty identifying genotype-phenotype correlations in this condition. Novel findings including the involvement of exon three in all compound heterozygous patients who suffered from cardiomyopathy, and the severity of mutations involving exons four and five may help to guide investigations and therapeutic decisions in an era of personalised medicine.
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Affiliation(s)
- Luke Carson
- School of Life Sciences, University of Nottingham, Nottingham, UK.
| | - Deborah Merrick
- School of Life Sciences, University of Nottingham, Nottingham, UK
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3
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Rocha CT, Escolar DM. Treatment and Management of Muscular Dystrophies. Neuromuscul Disord 2022. [DOI: 10.1016/b978-0-323-71317-7.00020-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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Alonso-Pérez J, González-Quereda L, Bruno C, Panicucci C, Alavi A, Nafissi S, Nilipour Y, Zanoteli E, de Augusto Isihi LM, Melegh B, Hadzsiev K, Muelas N, Vílchez JJ, Dourado ME, Kadem N, Kutluk G, Umair M, Younus M, Pegorano E, Bello L, Crawford TO, Suárez-Calvet X, Töpf A, Guglieri M, Marini-Bettolo C, Gallano P, Straub V, Díaz-Manera J. Clinical and genetic spectrum of a large cohort of patients with δ-sarcoglycan muscular dystrophy. Brain 2021; 145:596-606. [PMID: 34515763 PMCID: PMC9014751 DOI: 10.1093/brain/awab301] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/05/2021] [Accepted: 07/22/2021] [Indexed: 11/13/2022] Open
Abstract
Sarcoglycanopathies include four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. Delta-sarcoglycanopathy (LGMDR6) is the least frequent and is considered an ultra-rare disease. Our aim was to characterize the clinical and genetic spectrum of a large international cohort of LGMDR6 patients and to investigate whether or not genetic or protein expression data could predict diseasés severity. This is a retrospective study collecting demographic, genetic, clinical and histological data of patients with genetically confirmed LGMDR6 including protein expression data from muscle biopsies. We contacted 128 pediatric and adult neuromuscular units around the world that reviewed genetic data of patients with a clinical diagnosis of a neuromuscular disorder. We identified 30 patients with a confirmed diagnosis of LGMDR6 of which 23 patients were included in this study. Eighty seven percent of the patients had consanguineous parents. Ninety one percent of the patients were symptomatic at the time of the analysis. Proximal muscle weakness of the upper and lower limbs was the most common presenting symptom. Distal muscle weakness was observed early over the course of the disease in 56.5% of the patients. Cardiac involvement was reported in 5 patients (21.7%) and 4 patients (17.4%) required non-invasive ventilation. Sixty percent of patients were wheelchair-bound since early teens (median age of 12.0 years old). Patients with absent expression of the sarcoglycan complex on muscle biopsy had a significant earlier onset of symptoms and an earlier age of loss of ambulation compared to patients with residual protein expression. This study confirmed that delta-sarcoglycanopathy is an ultra-rare neuromuscular condition and described the clinical and molecular characteristics of the largest yet-reported collected cohort of patients. Our results showed that this is a very severe and quickly progressive disease characterized by generalized muscle weakness affecting predominantly proximal and distal muscles of the limbs. Similar to other forms of sarcoglycanopathies, the severity and rate of progressive weakness correlates inversely with the abundance of protein on muscle biopsy.
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Affiliation(s)
- Jorge Alonso-Pérez
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Departament of Medicine, Barcelona, 08041, Spain
| | - Lidia González-Quereda
- Genetics Department, IIB Sant Pau, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, 08041, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Spain
| | - Claudio Bruno
- Center of Translational and Experimental Myology, IRCSS Istituto Giannina Gaslini, Genova, 16147, Italy
| | - Chiara Panicucci
- Center of Translational and Experimental Myology, IRCSS Istituto Giannina Gaslini, Genova, 16147, Italy
| | - Afagh Alavi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, 13871, Iran
| | - Shahriar Nafissi
- Department of Neurology, Neuromuscular research center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, 14117, Iran
| | - Yalda Nilipour
- Pediatric Pathology Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, 14117, Iran
| | - Edmar Zanoteli
- Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, São Paulo, 05403, Brazil
| | - Lucas Michielon de Augusto Isihi
- Department of Neurology, Hospital das Clínicas HCFMUSP, Faculdade de Medicina da Universidade de São Paulo, São Paulo, 05403, Brazil
| | - Béla Melegh
- Department of Medical Genetics, and Szentagothai Research Center, University of Pecs, School of Medicine, Pecs, 07522, Hungary
| | - Kinga Hadzsiev
- Department of Medical Genetics, and Szentagothai Research Center, University of Pecs, School of Medicine, Pecs, 07522, Hungary
| | - Nuria Muelas
- Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Spain.,Neuromuscular Diseases Unit, Neurology Department, Hospital Universitari I Politècnic La Fe, Neuromuscular Reference Centre, ERN-EURO-NMD, Valencia, 46026, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, 46026, Spain
| | - Juan J Vílchez
- Genetics Department, IIB Sant Pau, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, 08041, Spain.,Neuromuscular and Ataxias Research Group, Instituto de Investigación Sanitaria La Fe, Valencia, 46026, Spain
| | - Mario Emilio Dourado
- Department of Integrative Medicine, Federal University of Rio Grande do Norte, Campus Universitário Lagoa Nova, 59012-300 Natal, RN, Brazil
| | - Naz Kadem
- University of Health Sciences, Antalya Research and Training Hospital, Department of Paediatric Neurology, Antalya, 07100, Turkey
| | - Gultekin Kutluk
- University of Health Sciences, Antalya Research and Training Hospital, Department of Paediatric Neurology, Antalya, 07100, Turkey
| | - Muhammad Umair
- Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard-Health Affairs (MNGHA), Riyadh, 14611, Saudi Arabia.,Department of Life Sciences, School of Science, University of Management and Technology (UMT), Lahore, 54770, Pakistan
| | - Muhammad Younus
- State Key Laboratory of Membrane Biology, Institute of Molecular Medicine, Beijing 100871, China
| | - Elena Pegorano
- Department of Neuroscience, University of Padova, Padova, 35112, Italy
| | - Luca Bello
- Department of Neuroscience, University of Padova, Padova, 35112, Italy
| | - Thomas O Crawford
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Xavier Suárez-Calvet
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Departament of Medicine, Barcelona, 08041, Spain
| | - Ana Töpf
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 3BZ, UK
| | - Michela Guglieri
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 3BZ, UK
| | - Chiara Marini-Bettolo
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 3BZ, UK
| | - Pia Gallano
- Genetics Department, IIB Sant Pau, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, 08041, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Spain
| | - Volker Straub
- The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 3BZ, UK
| | - Jordi Díaz-Manera
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Departament of Medicine, Barcelona, 08041, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Spain.,The John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 3BZ, UK
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Angelini C. LGMD. Identification, description and classification. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39:207-217. [PMID: 33458576 PMCID: PMC7783424 DOI: 10.36185/2532-1900-024] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 11/05/2022]
Abstract
The term ‘limb girdle muscular dystrophy’ (LGMD) was first used in the seminal paper by Walton and Nattrass in 1954, were they identified LGMD as a separate clinical entity In LGMD description it is pointed out that the category of LGMD most likely comprises a heterogeneous group of disorders. After that the clinical entity was discussed but the LMGD nosography reached a permanent classification during two ENMC workshops held in 1995 and 2017, in the last one an operating definition of LGMD was agreed. This last classification included dystrophies with proximal or distal-proximal presentation with evidence at biopsy of fibre degeneration and splitting, high CK, MRI imaging consistent with degenerative changes, fibro-fatty infiltration present in individuals that reached independent walking ability. To be considered in this group at least two unrelated families should be identified. A review is done of the first genetic characterisation of a number of LGMDs during the late twentieth century and a historical summary is given regarding how these conditions were clinically described and identified, the progresses done from identification of genetic loci, to protein and gene discoveries are reported. The LGMD described on which such historical progresses were done are the recessive calpainopathy (LGMD 2A/R1), dysferlinopathy (LGMD 2B/R2), sarcoglycanopathy (LGMD 2C-2F/R3-R6) types and the dominant type due to TPNO3 variants named transportinopathy (LGMD 1F/D2). Because of new diagnostic techniques such as exome and genome sequencing, it is likely that many other subtypes of LGMD might be identified in the future, however the lesson from the past discoveries can be useful for scientists and clinicians.
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Leyva-Leyva M, Sandoval A, Felix R, González-Ramírez R. Biochemical and Functional Interplay Between Ion Channels and the Components of the Dystrophin-Associated Glycoprotein Complex. J Membr Biol 2018; 251:535-550. [PMID: 29779049 DOI: 10.1007/s00232-018-0036-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 05/09/2018] [Indexed: 12/19/2022]
Abstract
Dystrophin is a cytoskeleton-linked membrane protein that binds to a larger multiprotein assembly called the dystrophin-associated glycoprotein complex (DGC). The deficiency of dystrophin or the components of the DGC results in the loss of connection between the cytoskeleton and the extracellular matrix with significant pathophysiological implications in skeletal and cardiac muscle as well as in the nervous system. Although the DGC plays an important role in maintaining membrane stability, it can also be considered as a versatile and flexible molecular complex that contribute to the cellular organization and dynamics of a variety of proteins at specific locations in the plasma membrane. This review deals with the role of the DGC in transmembrane signaling by forming supramolecular assemblies for regulating ion channel localization and activity. These interactions are relevant for cell homeostasis, and its alterations may play a significant role in the etiology and pathogenesis of various disorders affecting muscle and nerve function.
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Affiliation(s)
- Margarita Leyva-Leyva
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico
| | - Alejandro Sandoval
- Faculty of Superior Studies Iztacala, National Autonomous University of Mexico (UNAM), Tlalnepantla, Mexico
| | - Ricardo Felix
- Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City, Mexico.
| | - Ricardo González-Ramírez
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico.
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Ventura Spagnolo E, Mondello C, Di Mauro D, Vermiglio G, Asmundo A, Filippini E, Alibrandi A, Rizzo G. Analysis on sarcoglycans expression as markers of septic cardiomyopathy in sepsis-related death. Int J Legal Med 2018; 132:1685-1692. [PMID: 29644391 DOI: 10.1007/s00414-018-1840-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 04/03/2018] [Indexed: 11/28/2022]
Abstract
The post-mortem assessment of sepsis-related death can be carry out by many methods recently suggested as microbiological and biochemical investigations. In these cases, the cause of death is a multiple organ dysfunction due to a dysregulated inflammatory response occurring after the failure of infection control process. It was highlighted also that the heart can be a target organ in sepsis which determines the so-called septic cardiomyopathy characterized by myocardial depression. Several mechanisms to explain the pathophysiology of septic cardiomyopathy were suggested, but very few studies about the structural alterations of cardiac cells responsible for myocardial depression were carried out. The aim of this study was to evaluate whether sarcoglycans (SG) were involved in septic cardiac damage analyzing their expression in sepsis-related deaths and, particularly, if these proteins can be used as markers of septic myocardial dysfunction. Cases of septic-related death confirmed by clinical and autopsy records were investigated and compared to a control group of traumatic deaths. Indirect immunofluorescence analysis was performed to analyze α-SG, β-SG, δ-SG, ζ-SG, ε-SG, and γ-SG. Decrease of fluorescence staining pattern for all tested sarcoglycans was observed in the septic-related deaths compared to normal fluorescence staining pattern of control group. These results provide new findings about the myocytes structural alterations due to sepsis and suggest that these proteins could be used in forensic assessment of septic cardiomyopathy.
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Affiliation(s)
- Elvira Ventura Spagnolo
- Legal Medicine Section, Department for Health Promotion and Mother-Child Care, University of Palermo, Via del Vespro, 129, 90127, Palermo, Italy.
| | - Cristina Mondello
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
| | - Debora Di Mauro
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
| | - Giovanna Vermiglio
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
| | - Alessio Asmundo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
| | - Elena Filippini
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
| | - Angela Alibrandi
- Department of Economics, Unit of Statistical and Mathematical Sciences, University of Messina, Via dei Verdi 75, 98122, Messina, Italy
| | - Giuseppina Rizzo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, via Consolare Valeria, 1, 98125, Messina, Italy
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Bulakh MV, Ryzhkova OP, Polyakov AV. Sarcoglycanopathies: Clinical, Molecular and Genetic Characteristics, Epidemiology, Diagnostics and Treatment Options. RUSS J GENET+ 2018. [DOI: 10.1134/s1022795418020059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Bhat HF, Mir SS, Dar KB, Bhat ZF, Shah RA, Ganai NA. ABC of multifaceted dystrophin glycoprotein complex (DGC). J Cell Physiol 2017; 233:5142-5159. [DOI: 10.1002/jcp.25982] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/01/2017] [Indexed: 01/16/2023]
Affiliation(s)
- Hina F. Bhat
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
| | - Saima S. Mir
- Department of BiotechnologyUniversity of KashmirHazratbal, SrinagarJammu and KashmirIndia
| | - Khalid B. Dar
- Department of BiochemistryUniversity of KashmirHazratbal, SrinagarJammu and KashmirIndia
| | - Zuhaib F. Bhat
- Division of Livestock Products and TechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Jammu (SKUAST‐J), R.S. PoraJammuJammu and KashmirIndia
| | - Riaz A. Shah
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
| | - Nazir A. Ganai
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
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11
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12
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Waite AJ, Carlisle FA, Chan YM, Blake DJ. Myoclonus dystonia and muscular dystrophy: ɛ-sarcoglycan is part of the dystrophin-associated protein complex in brain. Mov Disord 2016; 31:1694-1703. [PMID: 27535350 PMCID: PMC5129563 DOI: 10.1002/mds.26738] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/24/2016] [Accepted: 06/27/2016] [Indexed: 11/17/2022] Open
Abstract
Background Myoclonus‐dystonia is a neurogenic movement disorder caused by mutations in the gene encoding ɛ‐sarcoglycan. By contrast, mutations in the α‐, β‐, γ‐, and δ‐sarcoglycan genes cause limb girdle muscular dystrophies. The sarcoglycans are part of the dystrophin‐associated protein complex in muscle that is disrupted in several types of muscular dystrophy. Intriguingly, patients with myoclonus‐dystonia have no muscle pathology; conversely, limb‐girdle muscular dystrophy patients have not been reported to have dystonia‐associated features. To gain further insight into the molecular mechanisms underlying these differences, we searched for evidence of a sarcoglycan complex in the brain. Methods Immunoaffinity chromatography and mass spectrometry were used to purify ubiquitous and brain‐specific ɛ‐sarcoglycan directly from tissue. Cell models were used to determine the effect of mutations on the trafficking and assembly of the brain sarcoglycan complex. Results Ubiquitous and brain‐specific ɛ‐sarcoglycan isoforms copurify with β‐, δ‐, and ζ‐sarcoglycan, β‐dystroglycan, and dystrophin Dp71 from brain. Incorporation of a muscular dystrophy‐associated β‐sarcoglycan mutant into the brain sarcoglycan complex impairs the formation of the βδ‐sarcoglycan core but fails to abrogate the association and membrane trafficking of ɛ‐ and ζ‐sarcoglycan. Conclusions ɛ‐Sarcoglycan is part of the dystrophin‐associated protein complex in brain. Partial preservation of ɛ‐ and ζ‐sarcoglycan in brain may explain the absence of myoclonus dystonia‐like features in muscular dystrophy patients. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Adrian J. Waite
- Division of Psychological Medicine and Clinical NeurosciencesMRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff UniversityCardiffUnited Kingdom
| | - Francesca A. Carlisle
- Division of Psychological Medicine and Clinical NeurosciencesMRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff UniversityCardiffUnited Kingdom
| | - Yiumo Michael Chan
- McColl‐Lockwood Laboratory for Muscular Dystrophy ResearchCarolinas Medical CenterCharlotteNorth CarolinaUSA
| | - Derek J. Blake
- Division of Psychological Medicine and Clinical NeurosciencesMRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff UniversityCardiffUnited Kingdom
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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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Nigro V, Piluso G. Spectrum of muscular dystrophies associated with sarcolemmal-protein genetic defects. Biochim Biophys Acta Mol Basis Dis 2014; 1852:585-93. [PMID: 25086336 DOI: 10.1016/j.bbadis.2014.07.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/19/2014] [Accepted: 07/23/2014] [Indexed: 01/31/2023]
Abstract
Muscular dystrophies are heterogeneous genetic disorders that share progressive muscle wasting. This may generate partial impairment of motility as well as a dramatic and fatal course. Less than 30 years ago, the identification of the genetic basis of Duchenne muscular dystrophy opened a new era. An explosion of new information on the mechanisms of disease was witnessed, with many thousands of publications and the characterization of dozens of other genetic forms. Genes mutated in muscular dystrophies encode proteins of the plasma membrane and extracellular matrix, several of which are part of the dystrophin-associated complex. Other gene products localize at the sarcomere and Z band, or are nuclear membrane components. In the present review, we focus on muscular dystrophies caused by defects that affect the sarcolemmal and sub-sarcolemmal proteins. We summarize the nature of each disease, the genetic cause, and the pathogenic pathways that may suggest future treatment options. We examine X-linked Duchenne and Becker muscular dystrophies and the autosomal recessive limb-girdle muscular dystrophies caused by mutations in genes encoding sarcolemmal proteins. The mechanism of muscle damage is reviewed starting from disarray of the shock-absorbing dystrophin-associated complex at the sarcolemma and activation of inflammatory response up to the final stages of fibrosis. We trace only a part of the biochemical, physiopathological and clinical aspects of muscular dystrophy to avoid a lengthy list of different and conflicting observations. We attempt to provide a critical synthesis of what we consider important aspects to better understand the disease. In our opinion, it is becoming ever more important to go back to the bedside to validate and then translate each proposed mechanism. This article is part of a Special Issue entitled: Neuromuscular Diseases: Pathology and Molecular Pathogenesis.
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Affiliation(s)
- Vincenzo Nigro
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, via Luigi De Crecchio 7, 80138 Napoli, Italy; Telethon Institute of Genetics and Medicine (TIGEM), via Pietro Castellino 111, 80131 Napoli, Italy.
| | - Giulio Piluso
- Dipartimento di Biochimica, Biofisica e Patologia Generale, Seconda Università degli Studi di Napoli, via Luigi De Crecchio 7, 80138 Napoli, Italy; Telethon Institute of Genetics and Medicine (TIGEM), via Pietro Castellino 111, 80131 Napoli, Italy
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Dystrophin complex functions as a scaffold for signalling proteins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:635-42. [DOI: 10.1016/j.bbamem.2013.08.023] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 08/22/2013] [Accepted: 08/28/2013] [Indexed: 11/23/2022]
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16
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Cutroneo G, Bramanti P, Favaloro A, Anastasi G, Trimarchi F, Di Mauro D, Rinaldi C, Speciale F, Inferrera A, Santoro G, Arena S, Patricolo M, Magno C. Sarcoglycan complex in human normal and pathological prostatic tissue: an immunohistochemical and RT-PCR study. Anat Rec (Hoboken) 2013; 297:327-36. [PMID: 24347395 DOI: 10.1002/ar.22846] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 11/03/2013] [Indexed: 11/11/2022]
Abstract
The sarcoglycan complex is a trans-membrane system playing a key role in mechano-signaling the connection from the cytoskeleton to the extracellular matrix. While b-, d-, and e-sarcoglycans are widely distributed, g- and a-sarcoglycans are expressed exclusively in skeletal and cardiac muscle. Insufficient data are available on the distribution of sarcoglycans in nonmuscular tissue. In the present study, we used immunohistochemical and RT-PCR techniques to study the sarcoglycans also in normal human glandular tissue, a type of tissue never studied in relation to the sarcoglycan complex, with the aim of verifying the real wider distribution of this complex. To understand the role of sarcoglycans, we tested specimens collected from patients affected by benign prostatic hyperplasia and adenocarcinoma. For the first time, our results showed that all sarcoglycans are detectable in normal samples both in epithelial and in myoepithelial cells; in pathological prostate, sarcoglycans appeared severely reduced in number or were absent. These data demonstrated that all sarcoglycans have a wider distribution suggesting a new unknown role for these proteins. The decreased number of sarcoglycans, containing cadherin domain homologs in samples of prostate affected by hyperplasia, and the absence of proteins in prostate biopsies, in cases affected by adenocarcinoma, could be responsible for the loss of adhesion between epithelial cells, which in turn facilitates the progression of benign tumors and the invasive potential of malignant tumors.
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Schröder NWJ, Grieben U, Prokop S, Dekomien G, Epplen JT, Heppner FL, Goebel HH, Stenzel W. Novel γ-sarcoglycan-mutation affects cardiac function and N-terminal dystrophin expression. Muscle Nerve 2013; 49:144-5. [PMID: 23929688 DOI: 10.1002/mus.23981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 07/22/2013] [Indexed: 11/07/2022]
Affiliation(s)
- Nicolas W J Schröder
- Department of Pathology, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
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Walko G, Wögenstein KL, Winter L, Fischer I, Feltri ML, Wiche G. Stabilization of the dystroglycan complex in Cajal bands of myelinating Schwann cells through plectin-mediated anchorage to vimentin filaments. Glia 2013; 61:1274-87. [PMID: 23836526 DOI: 10.1002/glia.22514] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Accepted: 03/28/2013] [Indexed: 11/06/2022]
Abstract
Previous studies have unmasked plectin, a uniquely versatile intermediate filament-associated cytolinker protein, to be essential for skin and skeletal muscle integrity. Different sets of isoforms of the protein were found to stabilize cells mechanically, regulate cytoskeletal dynamics, and serve as a scaffolding platform for signaling molecules. Here, we investigated whether a similar scenario prevails in myelinating Schwann cells. Using isoform-specific antibodies, the two plectin variants predominantly expressed in the cytoplasmic compartment (Cajal bands) of Schwann cells were identified as plectin (P)1 and P1c. Coimmunoprecipitation and immunolocalization experiments revealed complex formation of Cajal band plectin with β-dystroglycan, the core component of the dystrophin glycoprotein complex that in Schwann cells is crucial for the compartmentalization and stabilization of the myelin sheath. To study the functional implications of Schwann cell-specific plectin-β-dystroglycan interaction, we generated conditional (Schwann cell-restricted) plectin knockout mice. Ablation of plectin in myelinating Schwann cells (SCs) was found not to affect myelin sheath formation but to abrogate the tight association of the dystroglycan complex with the intermediate filament cytoskeleton. We show that the disruption of this association leads to the destabilization of the dystroglycan complex combined with increased myelin sheath deformations observed in the peripheral nerve during ageing of the animal.
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Affiliation(s)
- Gernot Walko
- Department of Biochemistry and Cell Biology, Max F. Perutz Laboratories, Center for Molecular Biology, University of Vienna, Vienna, Austria
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Martins PCM, Ayub-Guerrieri D, Martins-Bach AB, Onofre-Oliveira P, Malheiros JM, Tannus A, de Sousa PL, Carlier PG, Vainzof M. Dmdmdx/Largemyd: a new mouse model of neuromuscular diseases useful for studying physiopathological mechanisms and testing therapies. Dis Model Mech 2013; 6:1167-74. [PMID: 23798567 PMCID: PMC3759336 DOI: 10.1242/dmm.011700] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Although muscular dystrophies are among the most common human genetic disorders, there are few treatment options available. Animal models have become increasingly important for testing new therapies prior to entering human clinical trials. The Dmdmdx mouse is the most widely used animal model for Duchenne muscular dystrophy (DMD), presenting the same molecular and protein defect as seen in humans with the disease. However, this mouse is not useful for clinical trials because of its very mild phenotype. The mouse model for congenital myodystrophy type 1D, Largemyd, harbors a mutation in the glycosyltransferase Large gene and displays a severe phenotype. To help elucidate the role of the proteins dystrophin and LARGE in the organization of the dystrophin-glycoprotein complex in muscle sarcolemma, we generated double-mutant mice for the dystrophin and LARGE proteins. The new Dmdmdx/Largemyd mouse model is viable and shows a severe phenotype that is associated with the lack of dystrophin in muscle. We tested the usefulness of our new mouse model for cell therapy by systemically injecting them with normal murine mesenchymal adipose stem cells (mASCs). We verified that the mASCs were hosted in the dystrophic muscle. The new mouse model has proven to be very useful for the study of several other therapies, because injected cells can be screened both through DNA and protein analysis. Study of its substantial muscle weakness will also be very informative in the evaluation of functional benefits of these therapies.
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Affiliation(s)
- Poliana C M Martins
- Laboratory of Muscle Proteins and Comparative Histopathology, Human Genome Research Center, Biosciences Institute, University of São Paulo, São Paulo, Brazil
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21
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Rotundo IL, Lancioni A, Savarese M, D'Orsi L, Iacomino M, Nigro G, Piluso G, Auricchio A, Nigro V. Use of a lower dosage liver-detargeted AAV vector to prevent hamster muscular dystrophy. Hum Gene Ther 2013; 24:424-30. [PMID: 23427808 DOI: 10.1089/hum.2012.121] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The BIO14.6 hamster carries a mutation in the delta sarcoglycan gene causing muscular dystrophy and cardiomyopathy. The disease can be prevented by systemic delivery of delta sarcoglycan cDNA using adeno-associated viruses (AAVs). However, all AAVs also target the liver, raising concerns about their therapeutic efficacy in human applications. We compared the AAV2/8 with the chimeric AAV2/2i8, in which the 585-QQNTAP-590 motif of the AAV8 serotype was added to the heparan sulfate receptor footprint of the AAV2 strain. Both vectors carrying the human delta sarcoglycan cDNA were delivered into 24 14-day-old BIO14.6 hamsters. We followed transgene expression in muscle and liver for 7 months. We detected a sustained ectopic expression of delta sarcoglycan in the liver when using AAV2/8 but not AAV2/2i8. Genomic copies of AAV2/2i8 were not detectable in the liver, while at least 100-fold more copies of AAV2/8 were counted. In contrast, the hamster skeletal muscle expressed more delta sarcoglycan using AAV2/2i8 and were still healthy after 7 months at the lower dosage. We conclude that this chimeric vector is a robust option for safer and longer-term diseased muscle targeting.
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Affiliation(s)
- Ida Luisa Rotundo
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino 111, 80131 Napoli, Italy
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22
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Vitale JM, Schneider JS, Beck AJ, Zhao Q, Chang C, Gordan R, Michaels J, Bhaumik M, Fraidenraich D. Dystrophin-compromised sarcoglycan-δ-knockout diaphragm requires full wild-type embryonic stem cell reconstitution for correction. J Cell Sci 2012; 125:1807-13. [PMID: 22328522 DOI: 10.1242/jcs.100537] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Limb-girdle muscular dystrophy-2F (LGMD-2F) is an incurable degenerative muscle disorder caused by a mutation in the sarcoglycan-δ (SGδ)-encoding gene (SGCD in humans). The lack of SGδ results in the complete disruption of the sarcoglycan complex (SGC) in the skeletal and cardiac muscle within the larger dystrophin-glycoprotein complex (DGC). The long-term consequences of SG ablation on other members of the DGC are currently unknown. We produced mosaic mice through the injection of wild-type (WT) embryonic stem cells (ESCs) into SGδ-knockout (KO) blastocysts. ESC-derived SGδ was supplied to the sarcolemma of 18-month-old chimeric muscle, which resulted in the restoration of the SGC. Despite SGC rescue, and contrary to previous observations obtained with WT/mdx chimeras (a mouse rescue paradigm for Duchenne muscular dystrophy), low levels of ESC incorporation were insufficient to produce histological corrections in SGδ-KO skeletal muscle or heart. The inefficient process of ESC rescue was more evident in the SGδ-KO diaphragm, which had reduced levels of dystrophin and no compensatory utrophin, and needed almost full WT ESC reconstitution for histological improvement. The results suggest that the SGδ-KO mouse model of LGMD is not amenable to ESC treatment.
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Affiliation(s)
- Joseph M Vitale
- Department of Cell Biology and Molecular Medicine, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ 07107, USA
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23
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Arco A, Favaloro A, Gioffrè M, Santoro G, Speciale F, Vermiglio G, Cutroneo G. Sarcoglycans in the Normal and Pathological Breast Tissue of Humans: An Immunohistochemical and Molecular Study. Cells Tissues Organs 2012; 195:550-62. [DOI: 10.1159/000329508] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2011] [Indexed: 11/19/2022] Open
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Ng R, Banks GB, Hall JK, Muir LA, Ramos JN, Wicki J, Odom GL, Konieczny P, Seto J, Chamberlain JR, Chamberlain JS. Animal models of muscular dystrophy. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:83-111. [PMID: 22137430 DOI: 10.1016/b978-0-12-394596-9.00004-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The muscular dystrophies (MDs) represent a diverse collection of inherited human disorders, which affect to varying degrees skeletal, cardiac, and sometimes smooth muscle (Emery, 2002). To date, more than 50 different genes have been implicated as causing one or more types of MD (Bansal et al., 2003). In many cases, invaluable insights into disease mechanisms, structure and function of gene products, and approaches for therapeutic interventions have benefited from the study of animal models of the different MDs (Arnett et al., 2009). The large number of genes that are associated with MD and the tremendous number of animal models that have been developed preclude a complete discussion of each in the context of this review. However, we summarize here a number of the more commonly used models together with a mixture of different types of gene and MD, which serves to give a general overview of the value of animal models of MD for research and therapeutic development.
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Affiliation(s)
- Rainer Ng
- Division of Medical Genetics, Department of Neurology, University of Washington, Seattle, Washington, USA
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25
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Rotundo IL, Faraso S, De Leonibus E, Nigro G, Vitiello C, Lancioni A, Di Napoli D, Castaldo S, Russo V, Russo F, Piluso G, Auricchio A, Nigro V. Worsening of cardiomyopathy using deflazacort in an animal model rescued by gene therapy. PLoS One 2011; 6:e24729. [PMID: 21931833 PMCID: PMC3170375 DOI: 10.1371/journal.pone.0024729] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 08/16/2011] [Indexed: 01/04/2023] Open
Abstract
We have previously demonstrated that gene therapy can rescue the phenotype and extend lifespan in the delta-sarcoglycan deficient cardiomyopathic hamster. In patients with similar genetic defects, steroids have been largely used to slow down disease progression. Aim of our study was to evaluate the combined effects of steroid treatment and gene therapy on cardiac function. We injected the human delta-sarcoglycan cDNA by adeno-associated virus (AAV) 2/8 by a single intraperitoneal injection into BIO14.6 Syrian hamsters at ten days of age to rescue the phenotype. We then treated the hamsters with deflazacort. Treatment was administered to half of the hamsters that had received the AAV and the other hamsters without AAV, as well as to normal hamsters. Both horizontal and vertical activities were greatly enhanced by deflazacort in all groups. As in previous experiments, the AAV treatment alone was able to preserve the ejection fraction (70±7% EF). However, the EF value declined (52±14%) with a combination of AAV and deflazacort. This was similar with all the other groups of affected animals. We confirm that gene therapy improves cardiac function in the BIO14.6 hamsters. Our results suggest that deflazacort is ineffective and may also have a negative impact on the cardiomyopathy rescue, possibly by boosting motor activity. This is unexpected and may have significance in terms of the lifestyle recommendations for patients.
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Affiliation(s)
| | | | - Elvira De Leonibus
- Telethon Institute of Genetics and Medicine, Napoli, Italy
- Institute of Genetics and Biophysics, CNR, Napoli, Italy
| | - Gerardo Nigro
- A.O. Monaldi, Seconda Università di Napoli, Napoli, Italy
| | | | | | | | | | - Vincenzo Russo
- A.O. Monaldi, Seconda Università di Napoli, Napoli, Italy
| | - Fabio Russo
- Telethon Institute of Genetics and Medicine, Napoli, Italy
| | - Giulio Piluso
- Laboratorio di Genetica Medica, Dipartimento di Patologia Generale and CIRM, Seconda Università degli Studi di Napoli, Napoli, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine, Napoli, Italy
- Medical Genetics, Dipartimento di Pediatria, Università degli Studi di Napoli “Federico II”, Napoli, Italy
| | - Vincenzo Nigro
- Telethon Institute of Genetics and Medicine, Napoli, Italy
- Laboratorio di Genetica Medica, Dipartimento di Patologia Generale and CIRM, Seconda Università degli Studi di Napoli, Napoli, Italy
- * E-mail:
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Lancioni A, Rotundo IL, Kobayashi YM, D'Orsi L, Aurino S, Nigro G, Piluso G, Acampora D, Cacciottolo M, Campbell KP, Nigro V. Combined deficiency of alpha and epsilon sarcoglycan disrupts the cardiac dystrophin complex. Hum Mol Genet 2011; 20:4644-54. [PMID: 21890494 PMCID: PMC3209833 DOI: 10.1093/hmg/ddr398] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cardiomyopathy is a puzzling complication in addition to skeletal muscle pathology for patients with mutations in β-, γ- or δ-sarcoglycan (SG) genes. Patients with mutations in α-SG rarely have associated cardiomyopathy, or their cardiac pathology is very mild. We hypothesize that a fifth SG, ε-SG, may compensate for α-SG deficiency in the heart. To investigate the function of ε-SG in striated muscle, we generated an Sgce-null mouse and a Sgca-;Sgce-null mouse, which lacks both α- and ε-SGs. While Sgce-null mice showed a wild-type phenotype, with no signs of muscular dystrophy or heart disease, the Sgca-;Sgce-null mouse developed a progressive muscular dystrophy and a more anticipated and severe cardiomyopathy. It shows a complete loss of residual SGs and a strong reduction in both dystrophin and dystroglycan. Our data indicate that ε-SG is important in preventing cardiomyopathy in α-SG deficiency.
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Affiliation(s)
- Alessio Lancioni
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino 111, Napoli 80131, Italy
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27
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Blain AM, Straub VW. δ-Sarcoglycan-deficient muscular dystrophy: from discovery to therapeutic approaches. Skelet Muscle 2011; 1:13. [PMID: 21798091 PMCID: PMC3156636 DOI: 10.1186/2044-5040-1-13] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 03/17/2011] [Indexed: 11/10/2022] Open
Abstract
Mutations in the δ-sarcoglycan gene cause limb-girdle muscular dystrophy 2F (LGMD2F), an autosomal recessive disease that causes progressive weakness and wasting of the proximal limb muscles and often has cardiac involvement. Here we review the clinical implications of LGMD2F and discuss the current understanding of the putative mechanisms underlying its pathogenesis. Preclinical research has benefited enormously from various animal models of δ-sarcoglycan deficiency, which have helped researchers to explore therapeutic approaches for both muscular dystrophy and cardiomyopathy.
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Affiliation(s)
- Alison M Blain
- Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne, NE1 3BZ, UK
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Biomechanics of the sarcolemma and costameres in single skeletal muscle fibers from normal and dystrophin-null mice. J Muscle Res Cell Motil 2011; 31:323-36. [PMID: 21312057 DOI: 10.1007/s10974-011-9238-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Accepted: 01/11/2011] [Indexed: 01/01/2023]
Abstract
We studied the biomechanical properties of the sarcolemma and its links through costameres to the contractile apparatus in single mammalian myofibers of Extensor digitorum longus muscles isolated from wild (WT) and dystrophin-null (mdx) mice. Suction pressures (P) applied through a pipette to the sarcolemma generated a bleb, the height of which increased with increasing P. Larger increases in P broke the connections between the sarcolemma and myofibrils and eventually caused the sarcolemma to burst. We used the values of P at which these changes occurred to estimate the tensions and stiffness of the system and its individual elements. Tensions of the whole system and the sarcolemma, as well as the maximal tension sustained by the costameres, were all significantly lower (1.8-3.3 fold) in muscles of mdx mice compared to WT. Values of P at which separation and bursting occurred, as well as the stiffness of the whole system and of the isolated sarcolemma, were ~2-fold lower in mdx than in WT. Our results indicate that the absence of dystrophin reduces muscle stiffness, increases sarcolemmal deformability, and compromises the mechanical stability of costameres and their connections to nearby myofibrils.
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Abstract
The so-called sarcoglycanopathies form a subgroup of four genetically closely related autosomal recessive limb-girdle muscular dystrophies (LGMD2C-F) caused by mutations of the α-, β-, γ-, and δ-sarcoglycan genes. All four sarcoglycans are glycosylated transmembrane proteins and form a tetrameric complex that is part of dystrophin-associated proteins. The clinical phenotype associated with sarcoglycanopathies is characterized by a slowly progressive proximal muscle weakness with onset during childhood in most cases. The disease course is often similar but more variable than X-linked Duchenne muscular dystrophy. Diagnosis is usually based on muscle biopsy findings that confirm dystrophic changes and deficiency of one or more sarcoglycan proteins. Genetic testing is used to confirm the diagnosis. A number of different animal models have been developed to study the function of sarcoglycans and to develop specific therapeutic strategies such as gene transfer, but so far none of these techniques has entered clinical practice. Therefore, treatment is symptomatic and aims at amelioration of locomotor, respiratory, and cardiac manifestations of the disease.
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Affiliation(s)
- Janbernd Kirschner
- Division of Neuropediatrics and Muscle Disorders, University Medical Center Freiburg, Freiburg, Germany.
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30
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In dystrophic hamsters losartan affects control of ventilation and dopamine D1 receptor density. Respir Physiol Neurobiol 2010; 173:71-8. [PMID: 20601215 DOI: 10.1016/j.resp.2010.06.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Revised: 06/01/2010] [Accepted: 06/16/2010] [Indexed: 11/24/2022]
Abstract
The BIO 14.6 hamster (DV), an animal model of limb-girdle muscular dystrophy, has elevated angiotensin AT1 receptors that may affect ventilation. Moreover, AT1 receptors may modulate expression of dopamine D1 receptors. We investigated if chronic treatment of BIO 14.6 hamsters (DL) with losartan, an AT1 receptor blocker, affects D1 receptor density in the striatum and nucleus tractus solitarius (NTS) and normalizes ventilation during exposure to air, hypoxia, following hypoxia, and hypercapnia, Ventilation was evaluated using plethysmography. Compared to the golden Syrian hamsters (GS), DV hamsters exhibited lower hypercapnic and hypoxic responsiveness and ventilation during hypercapnic exposure. Relative to GS, DL hamsters increased breathing frequency in air and maintained ventilation during hypercapnia. Post-hypoxic minute ventilation decline occurred in DV but not in DL or GS hamsters. DL hamsters exhibited higher D1 receptor density in the striatum and NTS relative to DV hamsters. Thus, in dystrophic hamsters chronic losartan treatment stimulated frequency of breathing and increased the density of D1 receptors.
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Aquaporin expression in normal and pathological skeletal muscles: a brief review with focus on AQP4. J Biomed Biotechnol 2010; 2010:731569. [PMID: 20339523 PMCID: PMC2842974 DOI: 10.1155/2010/731569] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 01/12/2010] [Accepted: 01/17/2010] [Indexed: 11/30/2022] Open
Abstract
Freeze-fracture electron microscopy enabled us to observe the molecular architecture of the biological membranes. We were studying the myofiber plasma membranes of health and disease by using this technique and were interested in the special assembly called orthogonal arrays (OAs). OAs were present in normal myofiber plasma membranes and were especially numerous in fast twitch type 2 myofibers; while OAs were lost from sarcolemmal plasma membranes of severely affected muscles with dystrophinopathy and dysferlinopathy but not with caveolinopathy. In the mid nineties of the last century, the OAs turned out to be a water channel named aquaporin 4 (AQP4). Since this discovery, several groups of investigators have been studying AQP4 expression in diseased muscles. This review summarizes the papers which describe the expression of OAs, AQP4, and other AQPs at the sarcolemma of healthy and diseased muscle and discusses the possible role of AQPs, especially that of AQP4, in normal and pathological skeletal muscles.
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32
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Santoro L, Nolano M, Faraso S, Fiorillo C, Vitiello C, Provitera V, Aurino S, Nigro V. Perioral skin biopsy to study skeletal muscle protein expression. Muscle Nerve 2010; 41:392-8. [PMID: 20162678 DOI: 10.1002/mus.21506] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Clinical trials for muscular dystrophy molecular treatment require multiple sampling of skeletal muscle to monitor protein rescue. This practice is invasive and could raise ethical problems. A less invasive tool to obtain sequential muscle sampling is necessary. Using indirect immunofluorescence, we evaluated muscle protein expression in myofiber bundles included in 2-2.5-mm punch skin biopsies from the perioral region from 6 healthy subjects and 6 patients with genetically defined forms of muscular dystrophy. Large intradermal bundles of orbicularis oris muscle were constantly present in skin biopsies. They showed a typical muscular antigenic pattern in controls and the expected protein defect in muscular dystrophy patients. These results demonstrate the feasibility of muscular protein expression analysis using skin biopsy. We propose this minimally invasive technique to follow-up the response to genetic or conventional therapies in muscular dystrophies and to confirm the diagnosis in some special clinical conditions.
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Affiliation(s)
- Lucio Santoro
- Department of Neurological Sciences, University Federico II, Via Sergio Pansini 5, 80131 Naples, Italy.
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Ozawa E. Our trails and trials in the subsarcolemmal cytoskeleton network and muscular dystrophy researches in the dystrophin era. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2010; 86:798-821. [PMID: 20948175 PMCID: PMC3037518 DOI: 10.2183/pjab.86.798] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Accepted: 08/09/2010] [Indexed: 05/30/2023]
Abstract
In 1987, about 150 years after the discovery of Duchenne muscular dystrophy (DMD), its responsible gene, the dystrophin gene, was cloned by Kunkel. This was a new substance. During these 20 odd years after the cloning, our understanding on dystrophin as a component of the subsarcolemmal cytoskeleton networks and on the pathomechanisms of and experimental therapeutics for DMD has been greatly enhanced. During this paradigm change, I was fortunately able to work as an active researcher on its frontiers for 12 years. After we discovered that dystrophin is located on the cell membrane in 1988, we studied the architecture of dystrophin and dystrophin-associated proteins (DAPs) complex in order to investigate the function of dystrophin and pathomechanism of DMD. During the conduct of these studies, we came to consider that the dystrophin-DAP complex serves to transmembranously connect the subsarcolemmal cytoskeleton networks and basal lamina to protect the lipid bilayer. It then became our working hypothesis that injury of the lipid bilayer upon muscle contraction is the cause of DMD. During this process, we predicted that subunits of the sarcoglycan (SG) complex are responsible for respective types of DMD-like muscular dystrophy with autosomal recessive inheritance. Our prediction was confirmed to be true by many researchers including ourselves. In this review, I will try to explain what we observed and how we considered concerning the architecture and function of the dystrophin-DAP complex, and the pathomechanisms of DMD and related muscular dystrophies.
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Affiliation(s)
- Eijiro Ozawa
- National Center of Neuroscience, NCNP, Kodairashi, Tokyo 187-8502, Japan.
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Navarro C, Teijeira S. Molecular diagnosis of muscular dystrophies, focused on limb girdle muscular dystrophies. ACTA ACUST UNITED AC 2009; 3:631-47. [PMID: 23496048 DOI: 10.1517/17530050903313988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Muscular dystrophies include a spectrum of muscle disorders, some of which are phenotypically well characterized. The identification of dystrophin as the causative factor in Duchenne muscular dystrophy has led to the development of molecular genetics and has facilitated the division of muscular dystrophies into distinct groups, among which are the 'limb girdle muscular dystrophies'. OBJECTIVES This article reviews the methodology to be used in the diagnosis of muscular dystrophies, focused on the groups of limb girdle muscular dystrophies, and the development of new strategies to reach a final molecular diagnosis. METHOD A literature review (Medline) from 1985 to the present. CONCLUSION Immunohistochemistry and western blotting analyses of the proteins involved in the various forms of muscular dystrophies have permitted a refined pathological approach necessary to conduct genetic studies and to offer appropriate genetic counseling. The application of molecular medicine in genetic muscular dystrophies also brings great hope to the therapeutic management of these patients.
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Affiliation(s)
- Carmen Navarro
- University Hospital of Vigo, Department of Pathology and Neuropathology, Meixoeiro, s/n, 36200 Vigo - Pontevedra, Spain +34 986 81 11 11 ext. 211661 ; +34 986 27 64 16 ;
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Davis J, Westfall MV, Townsend D, Blankinship M, Herron TJ, Guerrero-Serna G, Wang W, Devaney E, Metzger JM. Designing heart performance by gene transfer. Physiol Rev 2008; 88:1567-651. [PMID: 18923190 DOI: 10.1152/physrev.00039.2007] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The birth of molecular cardiology can be traced to the development and implementation of high-fidelity genetic approaches for manipulating the heart. Recombinant viral vector-based technology offers a highly effective approach to genetically engineer cardiac muscle in vitro and in vivo. This review highlights discoveries made in cardiac muscle physiology through the use of targeted viral-mediated genetic modification. Here the history of cardiac gene transfer technology and the strengths and limitations of viral and nonviral vectors for gene delivery are reviewed. A comprehensive account is given of the application of gene transfer technology for studying key cardiac muscle targets including Ca(2+) handling, the sarcomere, the cytoskeleton, and signaling molecules and their posttranslational modifications. The primary objective of this review is to provide a thorough analysis of gene transfer studies for understanding cardiac physiology in health and disease. By comparing results obtained from gene transfer with those obtained from transgenesis and biophysical and biochemical methodologies, this review provides a global view of cardiac structure-function with an eye towards future areas of research. The data presented here serve as a basis for discovery of new therapeutic targets for remediation of acquired and inherited cardiac diseases.
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Affiliation(s)
- Jennifer Davis
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA
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36
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Gastaldello S, D'Angelo S, Franzoso S, Fanin M, Angelini C, Betto R, Sandonà D. Inhibition of proteasome activity promotes the correct localization of disease-causing alpha-sarcoglycan mutants in HEK-293 cells constitutively expressing beta-, gamma-, and delta-sarcoglycan. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:170-81. [PMID: 18535179 PMCID: PMC2438295 DOI: 10.2353/ajpath.2008.071146] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/27/2008] [Indexed: 11/20/2022]
Abstract
Sarcoglycanopathies are progressive muscle-wasting disorders caused by genetic defects of four proteins, alpha-, beta-, gamma-, and delta-sarcoglycan, which are elements of a key transmembrane complex of striated muscle. The proper assembly of the sarcoglycan complex represents a critical issue of sarcoglycanopathies, as several mutations severely perturb tetramer formation. Misfolded proteins are generally degraded through the cell's quality-control system; however, this can also lead to the removal of some functional polypeptides. To explore whether it is possible to rescue sarcoglycan mutants by preventing their degradation, we generated a heterologous cell system, based on human embryonic kidney (HEK) 293 cells, constitutively expressing three (beta, gamma, and delta) of the four sarcoglycans. In these betagammadelta-HEK cells, the lack of alpha-sarcoglycan prevented complex formation and cell surface localization, wheras the presence of alpha-sarcoglycan allowed maturation and targeting of the tetramer. As in muscles of sarcoglycanopathy patients, transfection of betagammadelta-HEK cells with disease-causing alpha-sarcoglycan mutants led to dramatic reduction of the mutated proteins and the absence of the complex from the cell surface. Proteasomal inhibition reduced the degradation of mutants and facilitated the assembly and targeting of the sarcoglycan complex to the plasma membrane. These data provide important insights for the potential development of pharmacological therapies for sarcoglycanopathies.
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37
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Trabelsi M, Kavian N, Daoud F, Commere V, Deburgrave N, Beugnet C, Llense S, Barbot JC, Vasson A, Kaplan JC, Leturcq F, Chelly J. Revised spectrum of mutations in sarcoglycanopathies. Eur J Hum Genet 2008; 16:793-803. [PMID: 18285821 DOI: 10.1038/ejhg.2008.9] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
To define the spectrum of mutations in alpha-, beta-, gamma-, and delta-sarcoglycan (SG) genes, we analyzed these genes in 69 probands with clinical and biological criteria compatible with the diagnosis of autosomal recessive limb-girdle muscular dystrophy. For 48 patients, muscle biopsies were available and multiplex western blot analysis of muscle proteins showed significant abnormalities of alpha- and gamma-SG. Our diagnostic strategy includes multiplex western blot, sequencing of SG genes, multiplex quantitative-fluorescent PCR and RT-PCR analyses. Mutations were detected in 57 patients and homozygous or compound heterozygous mutations were identified in 75% (36/48) of the patients with abnormal western blot, and in 52% (11/21) of the patients without muscle biopsy. Involvement of alpha-SG was demonstrated in 55.3% of cases (26/47), whereas gamma- and beta-SG were implicated in 25.5% (12/47) and in 17% (8/47) of cases, respectively. Interestingly, we identified 25 novel mutations, and a significant proportion of these mutations correspond to deletions (identified in 14 patients) of complete exon(s) of alpha- or gamma-SG genes, and partial duplications (identified in 5 patients) of exon 1 of beta-SG gene. This study highlights the high frequency of exonic deletions of alpha- and gamma-SG genes, as well as the presence of a hotspot of duplications affecting exon 1 of the beta-SG gene. In addition, protein analysis by multiplex western blot in combination with mutation screening and genotyping results allowed to propose a comprehensive and efficient diagnostic strategy and strongly suggested the implication of additional genes, yet to be identified, in sarcoglycanopathy-like disorders.
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Affiliation(s)
- Madiha Trabelsi
- Laboratoire de Biochimie Génétique et Moléculaire, Hôpital Cochin, Paris, France
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Ervasti JM, Sonnemann KJ. Biology of the striated muscle dystrophin-glycoprotein complex. INTERNATIONAL REVIEW OF CYTOLOGY 2008; 265:191-225. [PMID: 18275889 DOI: 10.1016/s0074-7696(07)65005-0] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Since its first description in 1990, the dystrophin-glycoprotein complex has emerged as a critical nexus for human muscular dystrophies arising from defects in a variety of distinct genes. Studies in mammals widely support a primary role for the dystrophin-glycoprotein complex in mechanical stabilization of the plasma membrane in striated muscle and provide hints for secondary functions in organizing molecules involved in cellular signaling. Studies in model organisms confirm the importance of the dystrophin-glycoprotein complex for muscle cell viability and have provided new leads toward a full understanding of its secondary roles in muscle biology.
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Affiliation(s)
- James M Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
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39
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Chen J, Skinner MA, Shi W, Yu QC, Wildeman AG, Chan YMM. The 16 kDa subunit of vacuolar H+-ATPase is a novel sarcoglycan-interacting protein. Biochim Biophys Acta Mol Basis Dis 2007; 1772:570-9. [PMID: 17382524 DOI: 10.1016/j.bbadis.2007.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Revised: 01/30/2007] [Accepted: 01/31/2007] [Indexed: 11/24/2022]
Abstract
The sarcoglycan complex in muscle consists of alpha-, beta-, gamma- and delta-sarcoglycan and is part of the larger dystrophin-glycoprotein complex (DGC), which is essential for maintaining muscle membrane integrity. Mutations in any of the four sarcoglycans cause limb-girdle muscular dystrophies (LGMD). In this report, we have identified a novel interaction between delta-sarcoglycan and the 16 kDa subunit c (16K) of vacuolar H(+)-ATPase. Co-expression studies in heterologous cell system revealed that 16K interacts specifically with delta-sarcoglycan and the highly related gamma-sarcoglycan through the transmembrane domains. In cultured C2C12 myotubes, 16K forms a complex with sarcoglycans at the plasma membrane. Loss of sarcoglycans in the sarcoglycan-deficient BIO14.6 hamster destabilizes the DGC and alters the localization of 16K at the sarcolemma. In addition, the steady state level of beta(1)-integrin is increased. Recent studies have shown that 16K also interacts directly with beta(1)-integrin and our data demonstrated that sarcoglycans, 16K and beta(1)-integrin were immunoprecipitated together in C2C12 myotubes. Since sarcoglycans have been proposed to participate in bi-directional signaling with integrins, our findings suggest that 16K might mediate the communication between sarcoglycans and integrins and play an important role in the pathogenesis of muscular dystrophy.
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Affiliation(s)
- Jiwei Chen
- Sigfried and Janet Weis Center for Research, The Geisinger Clinic, Danville, PA 17822, USA
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40
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Peter AK, Miller G, Crosbie RH. Disrupted mechanical stability of the dystrophin-glycoprotein complex causes severe muscular dystrophy in sarcospan transgenic mice. J Cell Sci 2007; 120:996-1008. [PMID: 17311848 DOI: 10.1242/jcs.03360] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The dystrophin-glycoprotein complex spans the muscle plasma membrane and provides a mechanical linkage between laminin in the extracellular matrix and actin in the intracellular cytoskeleton. Within the dystrophin-glycoprotein complex, the sarcoglycans and sarcospan constitute a subcomplex of transmembrane proteins that stabilize α-dystroglycan, a receptor for laminin and other components of the extracellular matrix. In order to elucidate the function of sarcospan, we generated transgenic mice that overexpress sarcospan in skeletal muscle. Sarcospan transgenic mice with moderate (tenfold) levels of sarcospan overexpression exhibit a severe phenotype that is similar to mouse models of laminin-deficient congenital muscular dystrophy (MD). Sarcospan transgenic mice display severe kyphosis and die prematurely between 6 and 10 weeks of age. Histological analysis reveals that sarcospan expression causes muscle pathology marked by increased muscle fiber degeneration and/or regeneration. Sarcospan transgenic muscle does not display sarcolemma damage, which is distinct from dystrophin- and sarcoglycan-deficient muscular dystrophies. We show that sarcospan clusters the sarcoglycans into insoluble protein aggregates and causes destabilization of α-dystroglycan. Evidence is provided to demonstrate abnormal extracellular matrix assembly, which represents a probable pathological mechanism for the severe and lethal dystrophic phenotype. Taken together, these data suggest that sarcospan plays an important mechanical role in stabilizing the dystrophin-glycoprotein complex.
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Affiliation(s)
- Angela K Peter
- Department of Physiological Science, University of California, Los Angeles, CA 90095, USA
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41
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Gouveia TLF, Kossugue PM, Paim JF, Zatz M, Anderson LVB, Nigro V, Vainzof M. A new evidence for the maintenance of the sarcoglycan complex in muscle sarcolemma in spite of the primary absence of δ-SG protein. J Mol Med (Berl) 2007; 85:415-20. [PMID: 17265058 DOI: 10.1007/s00109-007-0163-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 11/17/2006] [Accepted: 11/29/2006] [Indexed: 11/25/2022]
Abstract
delta-Sarcoglycan (delta-SG) is one of the first proteins of the sarcoglycan complex (SGC) to be expressed during muscle development, and it has been considered fundamental for the assembling and insertion of the SGC in the sarcolemma. Studies using heterologous cell systems and co-precipitation have demonstrated that SGC assembly was dependent on the simultaneous synthesis of all four sarcoglycan proteins. Mutations in any one of sarcoglycan genes, including the common disease causing mutation c.656delC in the delta-SG gene, block complex formation and its insertion in the plasma membrane. Failure in complex assembly in patients with this mutation would be therefore expected. In this study, we provide evidence for the possibility of preservation of part of the SG complex in the sarcolemma, even in the absence of delta-SG. This is based on the study of one mildly affected patient with limb-girdle muscular dystrophy type 2F (LGMD2F) due to the homozygous c.656delC mutation in the delta-SG gene. Protein analysis in his muscle biopsy presented a significant deficiency of only delta-SG with retention of the other three SG proteins in the sarcolemma. RNA expression analysis showed that zeta-SG, a functionally homologous to delta-SG, is not atypically upregulated in his muscle and would not replace the absent delta-SG, retaining the complex alpha-beta-gamma-zeta. The patient started clinical manifestation at age 25, with frequent falls, but he is currently able to walk unassisted at age 42. His clinical course is significantly milder when compared to several other affected patients carrying the same mutation associated with a total deficiency of the four SG proteins in the muscle studied by our group and confirmed in other patients. Therefore, our results add a new in vivo evidence that alpha-, beta-, and gamma-SG proteins can be maintained in the sarcolemma without delta-SG. Additionally, LGMD2F, with retention of the part of the SGC, might be associated to a milder clinical course, which has important implications for clinical prognosis and genetic counseling of the family.
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Affiliation(s)
- Telma L F Gouveia
- Departamento de Biologia, Centro de Estudos do Genoma Humano, IB, USP, Rua do Matão, 106, 05508-900, São Paulo, SP, Brazil
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42
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Esapa CT, Waite A, Locke M, Benson MA, Kraus M, McIlhinney RAJ, Sillitoe RV, Beesley PW, Blake DJ. SGCE missense mutations that cause myoclonus-dystonia syndrome impair ε-sarcoglycan trafficking to the plasma membrane: modulation by ubiquitination and torsinA. Hum Mol Genet 2007; 16:327-42. [PMID: 17200151 DOI: 10.1093/hmg/ddl472] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Myoclonus-dystonia syndrome (MDS) is a genetically heterogeneous disorder characterized by myoclonic jerks often seen in combination with dystonia and psychiatric co-morbidities and epilepsy. Mutations in the gene encoding epsilon-sarcoglycan (SGCE) have been found in some patients with MDS. SGCE is a maternally imprinted gene with the disease being inherited in an autosomal dominant pattern with reduced penetrance upon maternal transmission. In the central nervous system, epsilon-sarcoglycan is widely expressed in neurons of the cerebral cortex, basal ganglia, hippocampus, cerebellum and the olfactory bulb. epsilon-Sarcoglycan is located at the plasma membrane in neurons, muscle and transfected cells. To determine the effect of MDS-associated mutations on the function of epsilon-sarcoglycan we examined the biosynthesis and trafficking of wild-type and mutant proteins in cultured cells. In contrast to the wild-type protein, disease-associated epsilon-sarcoglycan missense mutations (H36P, H36R and L172R) produce proteins that are undetectable at the cell surface and are retained intracellularly. These mutant proteins become polyubiquitinated and are rapidly degraded by the proteasome. Furthermore, torsinA, that is mutated in DYT1 dystonia, a rare type of primary dystonia, binds to and promotes the degradation of epsilon-sarcoglycan mutants when both proteins are co-expressed. These data demonstrate that some MDS-associated mutations in SGCE impair trafficking of the mutant protein to the plasma membrane and suggest a role for torsinA and the ubiquitin proteasome system in the recognition and processing of misfolded epsilon-sarcoglycan.
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Affiliation(s)
- Christopher T Esapa
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
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43
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Piluso G, Politano L, Aurino S, Fanin M, Ricci E, Ventriglia VM, Belsito A, Totaro A, Saccone V, Topaloglu H, Nascimbeni AC, Fulizio L, Broccolini A, Canki-Klain N, Comi LI, Nigro G, Angelini C, Nigro V. Extensive scanning of the calpain-3 gene broadens the spectrum of LGMD2A phenotypes. J Med Genet 2006; 42:686-93. [PMID: 16141003 PMCID: PMC1736133 DOI: 10.1136/jmg.2004.028738] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The limb girdle muscular dystrophies (LGMD) are a heterogeneous group of Mendelian disorders highlighted by weakness of the pelvic and shoulder girdle muscles. Seventeen autosomal loci have been so far identified and genetic tests are mandatory to distinguish among the forms. Mutations at the calpain 3 locus (CAPN3) cause LGMD type 2A. OBJECTIVE To obtain unbiased information on the consequences of CAPN3 mutations. PATIENTS 530 subjects with different grades of symptoms and 300 controls. METHODS High throughput denaturing HPLC analysis of DNA pools. RESULTS 141 LGMD2A cases were identified, carrying 82 different CAPN3 mutations (45 novel), along with 18 novel polymorphisms/variants. Females had a more favourable course than males. In 94% of the more severely affected patient group, the defect was also discovered in the second allele. This proves the sensitivity of the approach. CAPN3 mutations were found in 35.1% of classical LGMD phenotypes. Mutations were also found in 18.4% of atypical patients and in 12.6% of subjects with high serum creatine kinase levels. CONCLUSIONS A non-invasive and cost-effective strategy, based on the high throughput denaturing HPLC analysis of DNA pools, was used to obtain unbiased information on the consequences of CAPN3 mutations in the largest genetic study ever undertaken. This broadens the spectrum of LGMD2A phenotypes and sets the carrier frequency at 1:103.
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Affiliation(s)
- G Piluso
- Dipartimento di Patologia Generale e Centro di Eccellenza per le malattie cardiovascolari, Seconda Università di Napoli, Naples, Italy
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Shiga K, Yoshioka H, Matsumiya T, Kimura I, Takeda S, Imamura M. ζ-Sarcoglycan is a functional homologue of γ-sarcoglycan in the formation of the sarcoglycan complex. Exp Cell Res 2006; 312:2083-92. [PMID: 16635485 DOI: 10.1016/j.yexcr.2006.03.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Revised: 03/06/2006] [Accepted: 03/08/2006] [Indexed: 11/28/2022]
Abstract
The sarcoglycans (SGs), transmembrane components of the dystrophin-associated glycoprotein complex, are stable and functional only when they assemble into a tetrameric complex in muscle cells. A defect in any one of the four SG members disrupts the entire SG complex (SGC) and causes limb-girdle muscular dystrophy. zeta-SG has been recently found as a transmembrane protein homologous to gamma-SG and delta-SG. To characterize zeta-SG in complex formation, we co-transfected expression vectors encoding all six SGs (alpha-, beta-, gamma-, delta-, epsilon- and zeta-SG) and dystroglycan into Chinese hamster ovary cells. Immunoprecipitation analysis showed that zeta-SG or gamma-SG formed a SGC with beta-SG and delta-SG plus alpha-SG or epsilon-SG, revealing that zeta-SG can form two types of SGCs (alpha-beta-zeta-delta or epsilon-beta-zeta-delta). This result indicates the functional resemblance of zeta-SG to gamma-SG rather than delta-SG, although phylogenetic analysis suggests that zeta-SG is evolutionally closer to delta-SG than to gamma-SG. Reverse transcription (RT)-PCR showed that the expression pattern of the transcript was almost the reciprocal of that of gamma-SG in various mouse tissues and that the zeta-SG transcript was especially abundant in the brain, suggesting that zeta-SG might play a particular role in the central nervous system.
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Affiliation(s)
- Kazuo Shiga
- Department of Molecular Therapy, National Institute of Neuroscience, NCNP, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8502, Japan
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45
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Ervasti JM. Dystrophin, its interactions with other proteins, and implications for muscular dystrophy. Biochim Biophys Acta Mol Basis Dis 2006; 1772:108-17. [PMID: 16829057 DOI: 10.1016/j.bbadis.2006.05.010] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 05/31/2006] [Accepted: 05/31/2006] [Indexed: 11/27/2022]
Abstract
Duchenne muscular dystrophy is the most prevalent and severe form of human muscular dystrophy. Investigations into the molecular basis for Duchenne muscular dystrophy were greatly facilitated by seminal studies in the 1980s that identified the defective gene and its major protein product, dystrophin. Biochemical studies revealed its tight association with a multi-subunit complex, the so-named dystrophin-glycoprotein complex. Since its description, the dystrophin-glycoprotein complex has emerged as an important structural unit of muscle and also as a critical nexus for understanding a diverse array of muscular dystrophies arising from defects in several distinct genes. The dystrophin homologue utrophin can compensate at the cell/tissue level for dystrophin deficiency, but functions through distinct molecular mechanisms of protein-protein interaction.
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Affiliation(s)
- James M Ervasti
- Department of Physiology, 127 Service Memorial Institute, University of Wisconsin Medical School, 1300 University Avenue, Madison, WI 53706, USA.
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Zeller R, Ivandic BT, Ehlermann P, Mücke O, Zugck C, Remppis A, Giannitsis E, Katus HA, Weichenhan D. Large-scale mutation screening in patients with dilated or hypertrophic cardiomyopathy: a pilot study using DGGE. J Mol Med (Berl) 2006; 84:682-91. [PMID: 16715312 DOI: 10.1007/s00109-006-0056-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2006] [Accepted: 02/28/2006] [Indexed: 01/21/2023]
Abstract
Cardiomyopathies are complex myocardial diseases characterized by inappropriate ventricular hypertrophy (HCM) or dilation (DCM). Both disorders may lead to sudden death or progressive heart failure and exhibit familial aggregation with marked genetic heterogeneity. Many candidate genes were identified by linkage analysis, experimental animal studies, and expression analysis. A systematic assessment of the prevalence of different mutations in these genes requires high-throughput analyses. In this paper, we present a simple and reliable protocol for mutation screening by heteroduplex analysis which reduced costs and workload of sequencing. Employing denaturing gradient gel electrophoresis (DGGE), 11 known and 14 potential candidate genes for HCM and DCM were analyzed. DGGE assays allowed analysis of 286 of the 312 protein coding exons, performing only four alternative polymerase chain reaction protocols and only two different DGGE analysis conditions. Sensitivity for the detection of heteroduplexes proved excellent, even for GC-rich DNA fragments, which were analyzed by a combination of DGGE and constant denaturant gel electrophoresis. To confirm DGGE sensitivity in cases where no variants in our human DNA samples could be observed, we generated heteroduplexes from homologous human and chimpanzee DNA. The platform proved a valuable contribution to elucidating the genetic causes of DCM and HCM as demonstrated by the identification of 17 different known and novel mutations and 98 different polymorphisms in our setting.
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Affiliation(s)
- Raphael Zeller
- Innere Medizin III, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
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Cheng L, Guo XF, Yang XY, Chong M, Cheng J, Li G, Gui YH, Lu DR. Delta-sarcoglycan is necessary for early heart and muscle development in zebrafish. Biochem Biophys Res Commun 2006; 344:1290-9. [PMID: 16650823 DOI: 10.1016/j.bbrc.2006.03.234] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2006] [Accepted: 03/31/2006] [Indexed: 10/24/2022]
Abstract
Delta-sarcoglycan, one member of the sarcoglycan complex, is a very conservative muscle-specific protein exclusively expressed in the skeletal and cardiac muscles of vertebrates. Mutations in sarcoglycans are known to be involved in limb-girdle muscular dystrophy (LGMD) and dilated cardiomyopathy (DCM) in humans. To address the role of delta-sarcoglycan gene in zebrafish development, we have studied expression pattern of delta-sarcoglycan in zebrafish embryos and examined the role of delta-sarcoglycan in zebrafish embryonic development by morpholino. Strong expression of delta-sarcoglycan was observed in various muscles including those of the segment, heart, eye, jaw, pectoral fin, branchial arches, and swim bladder in zebrafish embryo. Delta-sarcoglycan was also expressed in midbrain and retina. Knockdown of delta-sarcoglycan resulted in severe abnormality in both the cardiac and skeletal muscles. Some severe ones displayed serious morphological abnormality such as hypoplastic head, linear heart, very weak heartbeats, and runtish trunk, all dead within 5 dpf. Whole-mount in situ hybridization analysis showed that adaxial cells and muscle pioneers were affected in delta-sarcoglycan knockdown embryos. In addition, absence of delta-sarcoglycan protein severely delayed the cardiac development and influenced the differentiation of cardiac muscle, and the cardiac left-right asymmetry was dramatically changed in morpholino-treated embryos. These data together suggest that delta-sarcoglycan plays an important role in early heart and muscle development.
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Affiliation(s)
- Lu Cheng
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, PR China
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Hayashi K, Wakayama Y, Inoue M, Kojima H, Shibuya S, Jimi T, Hara H, Oniki H. Sarcospan: ultrastructural localization and its relation to the sarcoglycan subcomplex. Micron 2006; 37:591-6. [PMID: 16442802 DOI: 10.1016/j.micron.2005.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 11/23/2005] [Accepted: 11/24/2005] [Indexed: 11/18/2022]
Abstract
Sarcospan is a 25 kDa transmembrane component of dystrophin-associated glycoprotein. We generated a rabbit polyclonal antibody against synthetic peptide of the N-terminal domain of human sarcospan. Using this antibody we investigated the localization of sarcospan and its spacial relation to the components of sarcoglycan subcomplex in normal human skeletal myofibers by immunofluorescent microscopy and immunogold electron microscopy. In immunofluorescence the reaction was observed continuously at the myofiber surface. Ultrastructurally the gold signals of rabbit anti sarcospan antibody were present along the muscle plasma membrane, mainly at its inside surface. The triple immunogold labeled muscle samples showed that the signals of rabbit or sheep polyclonal anti alpha-, beta-, gamma- and delta-sarcoglycan antibodies and/or mouse monoclonal anti beta-, gamma- and delta-sarcoglycan antibodies were located along the muscle plasma membrane, and the cluster formation of different two or three sarcoglycan molecules was observed. The triple immunogold labeling also revealed that the signal of sarcospan molecules are present frequently in doublets and/or triplets with the components of sarcoglycan subcomplex, resulting in the cluster formation of signals of sarcoglycan and sarcospan molecules. The result of this study showed that sarcospan was expressed at the myofiber surface and that sarcospan was present in close association with alpha-, beta-, gamma- and delta-sarcoglycans and formed a functional unit with sarcoglycan subcomplex.
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Affiliation(s)
- Koutarou Hayashi
- Department of Neurology, Showa University Fujigaoka Hospital, Aoba-ku, Yokohama 227-8501, Japan
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Stabej P, Leegwater PAJ, Imholz S, Versteeg SA, Zijlstra C, Stokhof AA, Domanjko-Petriè A, van Oost BA. The canine sarcoglycan delta gene: BAC clone contig assembly, chromosome assignment and interrogation as a candidate gene for dilated cardiomyopathy in Dobermann dogs. Cytogenet Genome Res 2006; 111:140-6. [PMID: 16103655 DOI: 10.1159/000086383] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2004] [Accepted: 12/29/2004] [Indexed: 11/19/2022] Open
Abstract
Dilated cardiomyopathy (DCM) is a common disease of the myocardium recognized in human, dog and experimental animals. Genetic factors are responsible for a large proportion of cases in humans, and 17 genes with DCM causing mutations have been identified. The genetic origin of DCM in the Dobermann dogs has been suggested, but no disease genes have been identified to date. In this paper, we describe the characterization and evaluation of the canine sarcoglycan delta (SGCD), a gene implicated in DCM in human and hamster. Bacterial artificial chromosomes (BACs) containing the canine SGCD gene were isolated with probes for exon 3 and exons 4-8 and were characterized by Southern blot analysis. BAC end sequences were obtained for four BACs. Three of the BACs overlapped and could be ordered relative to each other and the end sequences of all four BACs could be anchored on the preliminary assembly of the dog genome sequence (www. ensembl.org). One of the BACs of the partial contig was localized by fluorescent in situ hybridization to canine chromosome 4q22, in agreement with the dog genome sequence. Two highly informative polymorphic microsatellite markers in intron 7 of the SGCD gene were identified. In 25 DCM-affected and 13 non DCM-affected dogs seven different haplotypes could be distinguished. However, no association between any of the SGCD variants and the disease locus was apparent.
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Affiliation(s)
- P Stabej
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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50
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Estrada FJ, Mornet D, Rosas-Vargas H, Angulo A, Hernández M, Becker V, Rendón A, Ramos-Kuri M, Coral-Vázquez RM. A novel isoform of delta-sarcoglycan is localized at the sarcoplasmic reticulum of mouse skeletal muscle. Biochem Biophys Res Commun 2005; 340:865-71. [PMID: 16403451 PMCID: PMC1952693 DOI: 10.1016/j.bbrc.2005.12.083] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2005] [Accepted: 12/12/2005] [Indexed: 11/22/2022]
Abstract
The sarcoglycan-sarcospan complex (alpha-, beta-, gamma-, delta-, epsilon-, and zeta-SG-SSPN), a component of the dystrophin-associated glycoprotein complex (DAGC), is located at the sarcolemma of muscle fibers where it contributes to maintain cell integrity during contraction-relaxation cycles; gamma- and delta-SG are also expressed in the sarcoplasmic reticulum (SR). In this study, we report the identification of a novel isoform of murine delta-SG produced by alternative splicing that we named delta-SG3. This isoform is present at transcript level in several tissues, with its highest expression in skeletal and cardiac muscle. The delta-SG3 protein lacks the last 122 amino acids at the C-terminal, which are replaced by 10 new amino acids (EGFLNMQLAG). Interestingly, double immunofluorescence analysis for delta-SG3 and the dihydropyridine receptor (DHPR) shows a close localization of these two proteins. We propose the subcellular distribution of this novel delta-SG3 isoform at the SR and its involvement in intracellular calcium concentration regulation.
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Affiliation(s)
- Francisco J. Estrada
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
- Laboratorio de Biologia Molecular
Escuela de Medicina Universidad PanamericanaMéxico y Escuela Nacional de Ciencias Biológicas-IPN,MX
| | - Dominique Mornet
- Muscles et pathologies chroniques
Université Montpellier I EA701Institut de Biologie, Boulevard Henry IV, 34062 Montpellier,FR
| | - Haydeé Rosas-Vargas
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
| | - Alexandra Angulo
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
| | - Manuel Hernández
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
| | - Viola Becker
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
| | - Alvaro Rendón
- Laboratoire de Physiopathologie Cellulaire et Moleculaire de la Retine
INSERM : U592Université Pierre et Marie Curie - Paris VIHopital Saint-Antoine PARIS VI
184, Rue du Faubourg Saint-Antoine
75571 PARIS CEDEX 12,FR
| | - Manuel Ramos-Kuri
- Laboratorio de Biologia Molecular
Escuela de Medicina Universidad PanamericanaMéxico y Escuela Nacional de Ciencias Biológicas-IPN,MX
| | - Ramón M. Coral-Vázquez
- Unidad de Investigacion Medica en Genetica Humana
Hospital de pediatria Centro Medico Nacional Siglo WXI-IMSSAv. Cuauhtémoc 330, Col. Doctores, C.P. 06725 México,MX
- * Correspondence should be adressed to: Ramón M. Coral-Vázquez
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