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Bhide S, Chandran S, Rajasekaran NS, Melkani GC. Genetic and Pathophysiological Basis of Cardiac and Skeletal Muscle Laminopathies. Genes (Basel) 2024; 15:1095. [PMID: 39202453 PMCID: PMC11354015 DOI: 10.3390/genes15081095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Revised: 08/14/2024] [Accepted: 08/15/2024] [Indexed: 09/03/2024] Open
Abstract
Nuclear lamins, a type V intermediate filament, are crucial components of the nuclear envelope's inner layer, maintaining nuclear integrity and mediating interactions between the nucleus and cytoplasm. Research on human iPSC-derived cells and animal models has demonstrated the importance of lamins in cardiac and skeletal muscle development and function. Mutations in lamins result in laminopathies, a group of diseases including muscular dystrophies, Hutchison-Gilford progeria syndrome, and cardiomyopathies with conduction defects. These conditions have been linked to disrupted autophagy, mTOR, Nrf2-Keap, and proteostasis signaling pathways, indicating complex interactions between the nucleus and cytoplasm. Despite progress in understanding these pathways, many questions remain about the mechanisms driving lamin-induced pathologies, leading to limited therapeutic options. This review examines the current literature on dysregulated pathways in cardiac and skeletal muscle laminopathies and explores potential therapeutic strategies for these conditions.
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Affiliation(s)
- Shruti Bhide
- Department of Biology, Molecular Biology Institute, San Diego State University, San Diego, CA 92182, USA; (S.B.); (S.C.)
| | - Sahaana Chandran
- Department of Biology, Molecular Biology Institute, San Diego State University, San Diego, CA 92182, USA; (S.B.); (S.C.)
| | - Namakkal S. Rajasekaran
- Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama, Birmingham, AL 35294, USA;
| | - Girish C. Melkani
- Department of Biology, Molecular Biology Institute, San Diego State University, San Diego, CA 92182, USA; (S.B.); (S.C.)
- Department of Pathology, Division of Molecular and Cellular Pathology, Heersink School of Medicine, University of Alabama, Birmingham, AL 35294, USA;
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2
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Wada E, Susumu N, Kaya M, Hayashi YK. Characteristics of nuclear architectural abnormalities of myotubes differentiated from Lmna H222P/H222P skeletal muscle cells. In Vitro Cell Dev Biol Anim 2024; 60:781-792. [PMID: 38724872 DOI: 10.1007/s11626-024-00915-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 04/22/2024] [Indexed: 08/03/2024]
Abstract
The presence of nuclear architectural abnormalities is a hallmark of the nuclear envelopathies, which are a group of diseases caused by mutations in genes encoding nuclear envelope proteins. Mutations in the lamin A/C gene cause several diseases, named laminopathies, including muscular dystrophies, progeria syndromes, and lipodystrophy. A mouse model carrying with the LmnaH222P/H222P mutation (H222P) was shown to develop severe cardiomyopathy but only mild skeletal myopathy, although abnormal nuclei were observed in their striated muscle. In this report, we analyzed the abnormal-shaped nuclei in myoblasts and myotubes isolated from skeletal muscle of H222P mice, and evaluated the expression of nuclear envelope proteins in these abnormal myonuclei. Primary skeletal muscle cells from H222P mice proliferated and efficiently differentiated into myotubes in vitro, similarly to those from wild-type mice. During cell proliferation, few abnormal-shaped nuclei were detected; however, numerous markedly abnormal myonuclei were observed in myotubes from H222P mice on days 5 and 7 of differentiation. Time-lapse observation demonstrated that myonuclei with a normal shape maintained their normal shape, whereas abnormal-shaped myonuclei remained abnormal for at least 48 h during differentiation. Among the abnormal-shaped myonuclei, 65% had a bleb with a string structure, and 35% were severely deformed. The area and nuclear contents of the nuclear blebs were relatively stable, whereas the myocytes with nuclear blebs were actively fused within primary myotubes. Although myonuclei were markedly deformed, the deposition of DNA damage marker (γH2AX) or apoptotic marker staining was rarely observed. Localizations of lamin A/C and emerin were maintained within the blebs, strings, and severely deformed regions of myonuclei; however, lamin B1, nesprin-1, and a nuclear pore complex protein were absent in these abnormal regions. These results demonstrate that nuclear membranes from H222P skeletal muscle cells do not rupture and are resistant to DNA damage, despite these marked morphological changes.
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Affiliation(s)
- Eiji Wada
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Nao Susumu
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Motoshi Kaya
- Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yukiko K Hayashi
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan.
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Zuela-Sopilniak N, Morival J, Lammerding J. Multi-level transcriptomic analysis of LMNA -related dilated cardiomyopathy identifies disease-driving processes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.11.598511. [PMID: 38915720 PMCID: PMC11195185 DOI: 10.1101/2024.06.11.598511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
LMNA- related dilated cardiomyopathy ( LMNA -DCM) is one of the most severe forms of DCM. The incomplete understanding of the molecular disease mechanisms results in lacking treatment options, leading to high mortality amongst patients. Here, using an inducible, cardiomyocyte-specific lamin A/C depletion mouse model, we conducted a comprehensive transcriptomic study, combining both bulk and single nucleus RNA sequencing, and spanning LMNA -DCM disease progression, to identify potential disease drivers. Our refined analysis pipeline identified 496 genes already misregulated early in disease. The expression of these genes was largely driven by disease specific cardiomyocyte sub-populations and involved biological processes mediating cellular response to DNA damage, cytosolic pattern recognition, and innate immunity. Indeed, DNA damage in LMNA -DCM hearts was significantly increased early in disease and correlated with reduced cardiomyocyte lamin A levels. Activation of cytosolic pattern recognition in cardiomyocytes was independent of cGAS, which is rarely expressed in cardiomyocytes, but likely occurred downstream of other pattern recognition sensors such as IFI16. Altered gene expression in cardiac fibroblasts and immune cell infiltration further contributed to tissue-wide changes in gene expression. Our transcriptomic analysis further predicted significant alterations in cell-cell communication between cardiomyocytes, fibroblasts, and immune cells, mediated through early changes in the extracellular matrix (ECM) in the LMNA -DCM hearts. Taken together, our work suggests a model in which nuclear damage in cardiomyocytes leads to activation of DNA damage responses, cytosolic pattern recognition pathway, and other signaling pathways that activate inflammation, immune cell recruitment, and transcriptional changes in cardiac fibroblasts, which collectively drive LMNA -DCM pathogenesis.
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Storey EC, Holt I, Brown S, Synowsky S, Shirran S, Fuller HR. Proteomic characterization of human LMNA-related congenital muscular dystrophy muscle cells. Neuromuscul Disord 2024; 38:26-41. [PMID: 38554696 DOI: 10.1016/j.nmd.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 04/02/2024]
Abstract
LMNA-related congenital muscular dystrophy (L-CMD) is caused by mutations in the LMNA gene, encoding lamin A/C. To further understand the molecular mechanisms of L-CMD, proteomic profiling using DIA mass spectrometry was conducted on immortalized myoblasts and myotubes from controls and L-CMD donors each harbouring a different LMNA mutation (R249W, del.32 K and L380S). Compared to controls, 124 and 228 differentially abundant proteins were detected in L-CMD myoblasts and myotubes, respectively, and were associated with enriched canonical pathways including synaptogenesis and necroptosis in myoblasts, and Huntington's disease and insulin secretion in myotubes. Abnormal nuclear morphology and reduced lamin A/C and emerin abundance was evident in all L-CMD cell lines compared to controls, while nucleoplasmic aggregation of lamin A/C was restricted to del.32 K cells, and mislocalization of emerin was restricted to R249W cells. Abnormal nuclear morphology indicates loss of nuclear lamina integrity as a common feature of L-CMD, likely rendering muscle cells vulnerable to mechanically induced stress, while differences between L-CMD cell lines in emerin and lamin A localization suggests that some molecular alterations in L-CMD are mutation specific. Nonetheless, identifying common proteomic alterations and molecular pathways across all three L-CMD lines has highlighted potential targets for the development of non-mutation specific therapies.
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Affiliation(s)
- Emily C Storey
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Ian Holt
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Sharon Brown
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK
| | - Silvia Synowsky
- BSRC Mass Spectrometry and Proteomics Facility, University of St Andrews, KY16 9ST, UK
| | - Sally Shirran
- BSRC Mass Spectrometry and Proteomics Facility, University of St Andrews, KY16 9ST, UK
| | - Heidi R Fuller
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, SY10 7AG, UK; The School of Pharmacy and Bioengineering, Keele University, ST5 5BG, UK.
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Mohar NP, Cox EM, Adelizzi E, Moore SA, Mathews KD, Darbro BW, Wallrath LL. The Influence of a Genetic Variant in CCDC78 on LMNA-Associated Skeletal Muscle Disease. Int J Mol Sci 2024; 25:4930. [PMID: 38732148 PMCID: PMC11084688 DOI: 10.3390/ijms25094930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/12/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024] Open
Abstract
Mutations in the LMNA gene-encoding A-type lamins can cause Limb-Girdle muscular dystrophy Type 1B (LGMD1B). This disease presents with weakness and wasting of the proximal skeletal muscles and has a variable age of onset and disease severity. This variability has been attributed to genetic background differences among individuals; however, such variants have not been well characterized. To identify such variants, we investigated a multigeneration family in which affected individuals are diagnosed with LGMD1B. The primary genetic cause of LGMD1B in this family is a dominant mutation that activates a cryptic splice site, leading to a five-nucleotide deletion in the mature mRNA. This results in a frame shift and a premature stop in translation. Skeletal muscle biopsies from the family members showed dystrophic features of variable severity, with the muscle fibers of some family members possessing cores, regions of sarcomeric disruption, and a paucity of mitochondria, not commonly associated with LGMD1B. Using whole genome sequencing (WGS), we identified 21 DNA sequence variants that segregate with the family members possessing more profound dystrophic features and muscle cores. These include a relatively common variant in coiled-coil domain containing protein 78 (CCDC78). This variant was given priority because another mutation in CCDC78 causes autosomal dominant centronuclear myopathy-4, which causes cores in addition to centrally positioned nuclei. Therefore, we analyzed muscle biopsies from family members and discovered that those with both the LMNA mutation and the CCDC78 variant contain muscle cores that accumulated both CCDC78 and RyR1. Muscle cores containing mislocalized CCDC78 and RyR1 were absent in the less profoundly affected family members possessing only the LMNA mutation. Taken together, our findings suggest that a relatively common variant in CCDC78 can impart profound muscle pathology in combination with a LMNA mutation and accounts for variability in skeletal muscle disease phenotypes.
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Affiliation(s)
- Nathaniel P. Mohar
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA; (N.P.M.); (E.A.)
- Department of Biochemistry and Molecular Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Efrem M. Cox
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA (S.A.M.)
- Department of Neurosurgery, UNLV School of Medicine, Las Vegas, NV 89106, USA
| | - Emily Adelizzi
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA; (N.P.M.); (E.A.)
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Steven A. Moore
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA (S.A.M.)
| | - Katherine D. Mathews
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Benjamin W. Darbro
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA; (N.P.M.); (E.A.)
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA;
| | - Lori L. Wallrath
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA; (N.P.M.); (E.A.)
- Department of Biochemistry and Molecular Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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Zhang Y, Ramirez-Martinez A, Chen K, McAnally JR, Cai C, Durbacz MZ, Chemello F, Wang Z, Xu L, Bassel-Duby R, Liu N, Olson EN. Net39 protects muscle nuclei from mechanical stress during the pathogenesis of Emery-Dreifuss muscular dystrophy. J Clin Invest 2023; 133:e163333. [PMID: 37395273 PMCID: PMC10313361 DOI: 10.1172/jci163333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 05/16/2023] [Indexed: 07/04/2023] Open
Abstract
Mutations in genes encoding nuclear envelope proteins lead to diseases known as nuclear envelopathies, characterized by skeletal muscle and heart abnormalities, such as Emery-Dreifuss muscular dystrophy (EDMD). The tissue-specific role of the nuclear envelope in the etiology of these diseases has not been extensively explored. We previously showed that global deletion of the muscle-specific nuclear envelope protein NET39 in mice leads to neonatal lethality due to skeletal muscle dysfunction. To study the potential role of the Net39 gene in adulthood, we generated a muscle-specific conditional knockout (cKO) of Net39 in mice. cKO mice recapitulated key skeletal muscle features of EDMD, including muscle wasting, impaired muscle contractility, abnormal myonuclear morphology, and DNA damage. The loss of Net39 rendered myoblasts hypersensitive to mechanical stretch, resulting in stretch-induced DNA damage. Net39 was downregulated in a mouse model of congenital myopathy, and restoration of Net39 expression through AAV gene delivery extended life span and ameliorated muscle abnormalities. These findings establish NET39 as a direct contributor to the pathogenesis of EDMD that acts by protecting against mechanical stress and DNA damage.
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Affiliation(s)
- Yichi Zhang
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Andres Ramirez-Martinez
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Kenian Chen
- Quantitative Biomedical Research Center, Peter O’Donnell Jr. School of Public Health, and
| | - John R. McAnally
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Chunyu Cai
- Department of Pathology, University of Texas (UT) Southwestern Medical Center, Dallas, Texas, USA
| | - Mateusz Z. Durbacz
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Francesco Chemello
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Zhaoning Wang
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Lin Xu
- Quantitative Biomedical Research Center, Peter O’Donnell Jr. School of Public Health, and
| | - Rhonda Bassel-Duby
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Ning Liu
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
| | - Eric N. Olson
- Department of Molecular Biology
- Hamon Center for Regenerative Science and Medicine
- Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center
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Battey E, Ross JA, Hoang A, Wilson DGS, Han Y, Levy Y, Pollock RD, Kalakoutis M, Pugh JN, Close GL, Ellison-Hughes GM, Lazarus NR, Iskratsch T, Harridge SDR, Ochala J, Stroud MJ. Myonuclear alterations associated with exercise are independent of age in humans. J Physiol 2023. [PMID: 36597809 DOI: 10.1113/jp284128] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 12/19/2022] [Indexed: 01/05/2023] Open
Abstract
Age-related decline in skeletal muscle structure and function can be mitigated by regular exercise. However, the precise mechanisms that govern this are not fully understood. The nucleus plays an active role in translating forces into biochemical signals (mechanotransduction), with the nuclear lamina protein lamin A regulating nuclear shape, nuclear mechanics and ultimately gene expression. Defective lamin A expression causes muscle pathologies and premature ageing syndromes, but the roles of nuclear structure and function in physiological ageing and in exercise adaptations remain obscure. Here, we isolated single muscle fibres and carried out detailed morphological and functional analyses on myonuclei from young and older exercise-trained individuals. Strikingly, myonuclei from trained individuals were more spherical, less deformable, and contained a thicker nuclear lamina than those from untrained individuals. Complementary to this, exercise resulted in increased levels of lamin A and increased myonuclear stiffness in mice. We conclude that exercise is associated with myonuclear remodelling, independently of age, which may contribute to the preservative effects of exercise on muscle function throughout the lifespan. KEY POINTS: The nucleus plays an active role in translating forces into biochemical signals. Myonuclear aberrations in a group of muscular dystrophies called laminopathies suggest that the shape and mechanical properties of myonuclei are important for maintaining muscle function. Here, striking differences are presented in myonuclear shape and mechanics associated with exercise, in both young and old humans. Myonuclei from trained individuals were more spherical, less deformable and contained a thicker nuclear lamina than untrained individuals. It is concluded that exercise is associated with age-independent myonuclear remodelling, which may help to maintain muscle function throughout the lifespan.
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Affiliation(s)
- E Battey
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
- British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, London, UK
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - J A Ross
- British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, London, UK
| | - A Hoang
- British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, London, UK
| | - D G S Wilson
- School of Engineering and Materials Science, Queen Mary University of London, London, UK
| | - Y Han
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - Y Levy
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - R D Pollock
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - M Kalakoutis
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
- Randall Centre for Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - J N Pugh
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - G L Close
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
| | - G M Ellison-Hughes
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - N R Lazarus
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - T Iskratsch
- School of Engineering and Materials Science, Queen Mary University of London, London, UK
- Randall Centre for Cell and Molecular Biophysics, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - S D R Harridge
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
| | - J Ochala
- Centre for Human & Applied Physiological Sciences, Faculty of Life Sciences & Medicine, King's College London, London, UK
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - M J Stroud
- British Heart Foundation Centre of Research Excellence, School of Cardiovascular Medicine and Sciences, King's College London, London, UK
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Genotype-Phenotype Correlations in Human Diseases Caused by Mutations of LINC Complex-Associated Genes: A Systematic Review and Meta-Summary. Cells 2022; 11:cells11244065. [PMID: 36552829 PMCID: PMC9777268 DOI: 10.3390/cells11244065] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/09/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Mutations in genes encoding proteins associated with the linker of nucleoskeleton and cytoskeleton (LINC) complex within the nuclear envelope cause different diseases with varying phenotypes including skeletal muscle, cardiac, metabolic, or nervous system pathologies. There is some understanding of the structure of LINC complex-associated proteins and how they interact, but it is unclear how mutations in genes encoding them can cause the same disease, and different diseases with different phenotypes. Here, published mutations in LINC complex-associated proteins were systematically reviewed and analyzed to ascertain whether patterns exist between the genetic sequence variants and clinical phenotypes. This revealed LMNA is the only LINC complex-associated gene in which mutations commonly cause distinct conditions, and there are no clear genotype-phenotype correlations. Clusters of LMNA variants causing striated muscle disease are located in exons 1 and 6, and metabolic disease-associated LMNA variants are frequently found in the tail of lamin A/C. Additionally, exon 6 of the emerin gene, EMD, may be a mutation "hot-spot", and diseases related to SYNE1, encoding nesprin-1, are most often caused by nonsense type mutations. These results provide insight into the diverse roles of LINC-complex proteins in human disease and provide direction for future gene-targeted therapy development.
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Autosomal dominant Emery-Dreifuss muscular dystrophy caused by a mutation in the lamin A/C gene identified by exome sequencing: a case report. BMC Pediatr 2022; 22:601. [PMID: 36253810 PMCID: PMC9575219 DOI: 10.1186/s12887-022-03662-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/10/2022] [Indexed: 11/16/2022] Open
Abstract
Background Emery-Dreifuss Muscular Dystrophy (EDMD) is an uncommon genetic disease among the group of muscular dystrophies. EDMD is clinically heterogeneous and resembles other muscular dystrophies. Mutation of the lamin A/C (LMNA) gene, which causes EDMD, also causes many other diseases. There is inter and intrafamilial variability in clinical presentations. Precise diagnosis can help in patient surveillance, especially before they present with cardiac problems. Hence, this paper shows how a molecular work-out by next-generation sequencing can help this group of disorders. Case presentation A 2-year-10-month-old Javanese boy presented to our clinic with weakness in lower limbs and difficulty climbing stairs. The clinical features of the boy were Gower's sign, waddling gait and high CK level. His father presented with elbow contractures and heels, toe walking and weakness of limbs, pelvic, and peroneus muscles. Exome sequencing on this patient detected a pathogenic variant in the LMNA gene (NM_170707: c.C1357T: NP_733821: p.Arg453Trp) that has been reported to cause Autosomal Dominant Emery-Dreifuss muscular dystrophy. Further examination showed total atrioventricular block and atrial fibrillation in the father. Conclusion EDMD is a rare disabling muscular disease that poses a diagnostic challenge. Family history work-up and thorough neuromuscular physical examinations are needed. Early diagnosis is essential to recognize orthopaedic and cardiac complications, improving the clinical management and prognosis of the disease. Exome sequencing could successfully determine pathogenic variants to provide a conclusive diagnosis.
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10
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Ganassi M, Muntoni F, Zammit PS. Defining and identifying satellite cell-opathies within muscular dystrophies and myopathies. Exp Cell Res 2022; 411:112906. [PMID: 34740639 PMCID: PMC8784828 DOI: 10.1016/j.yexcr.2021.112906] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 10/12/2021] [Accepted: 10/29/2021] [Indexed: 12/19/2022]
Abstract
Muscular dystrophies and congenital myopathies arise from specific genetic mutations causing skeletal muscle weakness that reduces quality of life. Muscle health relies on resident muscle stem cells called satellite cells, which enable life-course muscle growth, maintenance, repair and regeneration. Such tuned plasticity gradually diminishes in muscle diseases, suggesting compromised satellite cell function. A central issue however, is whether the pathogenic mutation perturbs satellite cell function directly and/or indirectly via an increasingly hostile microenvironment as disease progresses. Here, we explore the effects on satellite cell function of pathogenic mutations in genes (myopathogenes) that associate with muscle disorders, to evaluate clinical and muscle pathological hallmarks that define dysfunctional satellite cells. We deploy transcriptomic analysis and comparison between muscular dystrophies and myopathies to determine the contribution of satellite cell dysfunction using literature, expression dynamics of myopathogenes and their response to the satellite cell regulator PAX7. Our multimodal approach extends current pathological classifications to define Satellite Cell-opathies: muscle disorders in which satellite cell dysfunction contributes to pathology. Primary Satellite Cell-opathies are conditions where mutations in a myopathogene directly affect satellite cell function, such as in Progressive Congenital Myopathy with Scoliosis (MYOSCO) and Carey-Fineman-Ziter Syndrome (CFZS). Primary satellite cell-opathies are generally characterised as being congenital with general hypotonia, and specific involvement of respiratory, trunk and facial muscles, although serum CK levels are usually within the normal range. Secondary Satellite Cell-opathies have mutations in myopathogenes that affect both satellite cells and muscle fibres. Such classification aids diagnosis and predicting probable disease course, as well as informing on treatment and therapeutic development.
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Affiliation(s)
- Massimo Ganassi
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, SE1 1UL, UK.
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, United Kingdom; NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, United Kingdom
| | - Peter S Zammit
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, SE1 1UL, UK.
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11
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Świątkowska-Flis B, Zdolińska-Malinowska I, Sługocka D, Boruczkowski D. The use of umbilical cord-derived mesenchymal stem cells in patients with muscular dystrophies: Results from compassionate use in real-life settings. Stem Cells Transl Med 2021; 10:1372-1383. [PMID: 34313400 PMCID: PMC8459640 DOI: 10.1002/sctm.21-0027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/10/2021] [Accepted: 06/16/2021] [Indexed: 12/15/2022] Open
Abstract
Muscular dystrophies are genetically determined progressive diseases with no cause‐related treatment and limited supportive treatment. Although stem cells cannot resolve the underlying genetic conditions, their wide‐ranging therapeutic properties may ameliorate the consequences of the involved mutations (oxidative stress, inflammation, mitochondrial dysfunction, necrosis). In this study, we administered advanced therapy medicinal product containing umbilical cord‐derived mesenchymal stem cells (UC‐MSCs) to 22 patients with muscular dystrophies. Patients received one to five intravenous and/or intrathecal injections per treatment course in up to two courses every 2 months. Four standard doses of 10, 20, 30, or 40 × 106 UC‐MSCs per injection were used; the approximate dose per kilogram was 1 × 106 UC‐MSCs. Muscle strength was measured with a set of CQ Dynamometer computerized force meters (CQ Elektronik System, Czernica, Poland). Statistical analysis of muscle strength in the whole group showed significant improvement in the right upper limb (+4.0 N); left hip straightening (+4.5 N) and adduction (+0.5 N); right hip straightening (+1.0 N), bending (+7.5 N), and adduction (+2.5 N); right knee straightening (+8.5 N); left shoulder revocation (+13.0 N), straightening (+5.5 N), and bending (+6.5 N); right shoulder adduction (+3.0 N), revocation (+10.5 N), and bending (+5 N); and right elbow straightening (+9.5 N); all these differences were statistically significant. In six patients (27.3%) these changes led to improvement in gait analysis or movement scale result. Only one patient experienced transient headache and lower back pain after the last administration. In conclusion, UC‐MSC therapy may be considered as a therapeutic option for these patients.
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Affiliation(s)
- Beata Świątkowska-Flis
- Polish Center of Cell Therapy and Immunotherapy in Częstochowa, CM Klara, Częstochowa, Poland.,Faculty of Health Sciences, Jan Długosz University of Humanities and Life Sciences, Częstochowa, Poland
| | | | - Dominika Sługocka
- Polish Center of Cell Therapy and Immunotherapy in Częstochowa, CM Klara, Częstochowa, Poland
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12
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Earle AJ, Kirby TJ, Fedorchak GR, Isermann P, Patel J, Iruvanti S, Moore SA, Bonne G, Wallrath LL, Lammerding J. Mutant lamins cause nuclear envelope rupture and DNA damage in skeletal muscle cells. NATURE MATERIALS 2020; 19:464-473. [PMID: 31844279 PMCID: PMC7102937 DOI: 10.1038/s41563-019-0563-5] [Citation(s) in RCA: 135] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 11/12/2019] [Indexed: 05/19/2023]
Abstract
Mutations in the LMNA gene, which encodes the nuclear envelope (NE) proteins lamins A/C, cause Emery-Dreifuss muscular dystrophy, congenital muscular dystrophy and other diseases collectively known as laminopathies. The mechanisms responsible for these diseases remain incompletely understood. Using three mouse models of muscle laminopathies and muscle biopsies from individuals with LMNA-related muscular dystrophy, we found that Lmna mutations reduced nuclear stability and caused transient rupture of the NE in skeletal muscle cells, resulting in DNA damage, DNA damage response activation and reduced cell viability. NE and DNA damage resulted from nuclear migration during skeletal muscle maturation and correlated with disease severity in the mouse models. Reduction of cytoskeletal forces on the myonuclei prevented NE damage and rescued myofibre function and viability in Lmna mutant myofibres, indicating that myofibre dysfunction is the result of mechanically induced NE damage. Taken together, these findings implicate mechanically induced DNA damage as a pathogenic contributor to LMNA skeletal muscle diseases.
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Affiliation(s)
- Ashley J Earle
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Tyler J Kirby
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Gregory R Fedorchak
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Philipp Isermann
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Jineet Patel
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Sushruta Iruvanti
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Steven A Moore
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Gisèle Bonne
- Sorbonne Université, Inserm UMRS 974, Center of Research in Myology, Association Institute of Myology, Paris, France
| | - Lori L Wallrath
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Jan Lammerding
- Meinig School of Biomedical Engineering & Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA.
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13
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Maffioletti SM, Sarcar S, Henderson ABH, Mannhardt I, Pinton L, Moyle LA, Steele-Stallard H, Cappellari O, Wells KE, Ferrari G, Mitchell JS, Tyzack GE, Kotiadis VN, Khedr M, Ragazzi M, Wang W, Duchen MR, Patani R, Zammit PS, Wells DJ, Eschenhagen T, Tedesco FS. Three-Dimensional Human iPSC-Derived Artificial Skeletal Muscles Model Muscular Dystrophies and Enable Multilineage Tissue Engineering. Cell Rep 2019; 23:899-908. [PMID: 29669293 PMCID: PMC5917451 DOI: 10.1016/j.celrep.2018.03.091] [Citation(s) in RCA: 194] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/21/2018] [Accepted: 03/20/2018] [Indexed: 01/07/2023] Open
Abstract
Generating human skeletal muscle models is instrumental for investigating muscle pathology and therapy. Here, we report the generation of three-dimensional (3D) artificial skeletal muscle tissue from human pluripotent stem cells, including induced pluripotent stem cells (iPSCs) from patients with Duchenne, limb-girdle, and congenital muscular dystrophies. 3D skeletal myogenic differentiation of pluripotent cells was induced within hydrogels under tension to provide myofiber alignment. Artificial muscles recapitulated characteristics of human skeletal muscle tissue and could be implanted into immunodeficient mice. Pathological cellular hallmarks of incurable forms of severe muscular dystrophy could be modeled with high fidelity using this 3D platform. Finally, we show generation of fully human iPSC-derived, complex, multilineage muscle models containing key isogenic cellular constituents of skeletal muscle, including vascular endothelial cells, pericytes, and motor neurons. These results lay the foundation for a human skeletal muscle organoid-like platform for disease modeling, regenerative medicine, and therapy development. Human iPSC-derived 3D artificial muscles show features of normal skeletal muscle Multiple muscular dystrophy iPSC lines can be differentiated in 3D artificial muscles Artificial muscle constructs model severe, incurable forms of muscular dystrophy Isogenic vascular-like networks and motor neurons develop within artificial muscles
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Affiliation(s)
| | - Shilpita Sarcar
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Alexander B H Henderson
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Ingra Mannhardt
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf (UKE), 20246 Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Germany
| | - Luca Pinton
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK; Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Louise Anne Moyle
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Heather Steele-Stallard
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK; Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Ornella Cappellari
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK
| | - Kim E Wells
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK
| | - Giulia Ferrari
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Jamie S Mitchell
- Institute of Neurology, University College London, London WC1N 3BG, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Giulia E Tyzack
- Institute of Neurology, University College London, London WC1N 3BG, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Vassilios N Kotiadis
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Moustafa Khedr
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Martina Ragazzi
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Weixin Wang
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Michael R Duchen
- Department of Cell and Developmental Biology, University College London, London WC1E 6DE, UK
| | - Rickie Patani
- Institute of Neurology, University College London, London WC1N 3BG, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Peter S Zammit
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Dominic J Wells
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK
| | - Thomas Eschenhagen
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg Eppendorf (UKE), 20246 Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Germany
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14
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Wada E, Kato M, Yamashita K, Kokuba H, Liang WC, Bonne G, Hayashi YK. Deficiency of emerin contributes differently to the pathogenesis of skeletal and cardiac muscles in LmnaH222P/H222P mutant mice. PLoS One 2019; 14:e0221512. [PMID: 31430335 PMCID: PMC6701770 DOI: 10.1371/journal.pone.0221512] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/08/2019] [Indexed: 11/18/2022] Open
Abstract
Laminopathies are tissue-selective diseases that affect differently in organ systems. Mutations in nuclear envelopes, emerin (Emd) and lamin A/C (Lmna) genes, cause clinically indistinguishable myopathy called Emery-Dreifuss muscular dystrophy (EDMD) and limb-girdle muscular dystrophy. Several murine models for EDMD have been generated; however, emerin-null (Emd) mice do not show obvious skeletal and cardiac muscle phenotypes, and Lmna H222P/H222P mutant (H222P) mice show only a mild phenotype in skeletal muscle when they already have severe cardiomyopathy. Thus, the underlying molecular mechanism of muscle involvement due to nuclear abnormalities is still unclarified. We generated double mutant (Emd-/-/LmnaH222P/H222P; EH) mice to characterize dystrophic changes and to elucidate interactions between emerin and lamin A/C in skeletal and cardiac muscles. As H222P mice, EH mice grow normally and have breeding productivity. EH mice showed severer muscle involvement compared with that of H222P mice which was an independent of cardiac abnormality at 12 weeks of age. Nuclear abnormalities, reduced muscle fiber size and increased fibrosis were prominent in EH mice. Roles of emerin and lamin A/C in satellite cells function and regeneration of muscle fiber were also evaluated by cardiotoxin-induced muscle injury. Delayed increases in myog and myh3 expression were seen in both H222P and EH mice; however, the expression levels of those genes were similar with control and regenerated muscle fiber size was not different at day 7 after injury. These results indicate that EH mouse is a suitable model for studying skeletal muscle involvement, independent of cardiac function, in laminopathies and an interaction between emerin and lamin A/C in different tissues.
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Affiliation(s)
- Eiji Wada
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Megumi Kato
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Kaori Yamashita
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
| | - Hiroko Kokuba
- Institute of Medical Science, Tokyo Medical University, Tokyo, Japan
| | - Wen-Chen Liang
- Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Gisèle Bonne
- Sorbonne Université, Inserm UMRS 974, Center of Research in Myology, Paris, France
| | - Yukiko K. Hayashi
- Department of Pathophysiology, Tokyo Medical University, Tokyo, Japan
- * E-mail:
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15
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Cotta A, Paim JF, Carvalho E, Valicek J, da Cunha Junior AL, Navarro MM, Vargas AP, Lima MI, de Almeida CF, Takata RI, Vainzof M. LMNA-Related Muscular Dystrophy with Clinical Intrafamilial Variability. J Mol Neurosci 2019; 69:623-627. [PMID: 31410651 DOI: 10.1007/s12031-019-01390-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 07/18/2019] [Indexed: 10/26/2022]
Abstract
The LMNA gene is associated to a huge broad of phenotypes, including congenital Emery-Dreifuss muscular dystrophy and late-onset LMNA-related muscular dystrophy. In these forms, muscle weakness, contractures, and cardiac impairment are common. In an autosomal dominant pedigree including 5 affected patients, NGS molecular analysis performed in 6 relatives identifies the heterozygous c.1129C>T p.Arg377Cys variant in the exon 6 of the LMNA gene in three of them. Clinical, laboratorial, imaging investigation of these affected patients showed a significant clinical variability: the father presented subclinical imaging muscular dystrophy masqueraded as radiculopathy. One of his sons presented cardiac arrhythmia, muscular weakness, elbow contractures, and intranuclear pseudoinclusions on muscle biopsy. A second son presented only decreased tendon reflexes. Two other brothers presenting myalgia and cramps were not carriers of the same mutation in the LMNA gene. Early diagnosis, considering these variable phenotype and genotype, is important for genetic counseling, as well as cardiac, and rehabilitation management.
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Affiliation(s)
- Ana Cotta
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Julia F Paim
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Elmano Carvalho
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Jaquelin Valicek
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Antonio L da Cunha Junior
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Monica M Navarro
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Antonio P Vargas
- Pathology, Neurophysiology, Radiology, Pediatrics and Genetics, and Neurology Departments, SARAH Network of Rehabilitation Hospitals, Belo Horizonte, Brazil
| | - Maria I Lima
- Electron Microscopy and Molecular Biology Departments, SARAH Network of Rehabilitation Hospitals, Brasilia, Brazil
| | - Camila F de Almeida
- Human Genome and Stem Cells Research Center, Genetics and Evolutionary Biology Department, IBUSP, University of São Paulo, Rua do Matão, Travessa 13, no. 106, São Paulo, SP, 05508-090, Brazil
| | - Reinaldo I Takata
- Electron Microscopy and Molecular Biology Departments, SARAH Network of Rehabilitation Hospitals, Brasilia, Brazil
| | - Mariz Vainzof
- Human Genome and Stem Cells Research Center, Genetics and Evolutionary Biology Department, IBUSP, University of São Paulo, Rua do Matão, Travessa 13, no. 106, São Paulo, SP, 05508-090, Brazil.
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16
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Castillo-Iglesias MS, Berciano MT, Narcis JO, Val-Bernal JF, Rodriguez-Rey JC, Tapia O, Lafarga M. Reorganization of the nuclear compartments involved in transcription and RNA processing in myonuclei of type I spinal muscular atrophy. Histochem Cell Biol 2019; 152:227-237. [PMID: 31183542 DOI: 10.1007/s00418-019-01792-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2019] [Indexed: 01/01/2023]
Abstract
Type I spinal muscular atrophy (SMA) is an autosomal recessive disorder caused by the loss or mutation of the survival motor neuron 1 (SMN1) gene. The reduction in SMN protein levels in SMA leads to the degeneration of motor neurons and muscular atrophy. In this study, we analyzed the nuclear reorganization in human skeletal myofibers from a type I SMA patient carrying a deletion of exons 7 and 8 in the SMN1 gene and two SMN2 gene copies and showing reduced SMN protein levels in the muscle compared with those in control samples. The morphometric analysis of myofiber size revealed the coexistence of atrophic and hypertrophic myofibers in SMA samples. Compared with controls, both nuclear size and the nuclear shape factor were significantly reduced in SMA myonuclei. Nuclear reorganization in SMA myonuclei was characterized by extensive heterochromatinization, the aggregation of splicing factors in large interchromatin granule clusters, and nucleolar alterations with the accumulation of the granular component and a loss of fibrillar center/dense fibrillar component units. These nuclear alterations reflect a severe perturbation of global pre-mRNA transcription and splicing, as well as nucleolar dysfunction, in SMA myofibers. Moreover, the finding of similar nuclear reorganization in both atrophic and hypetrophic myofibers provides additional support that the SMN deficiency in SMA patients may primarily affect the skeletal myofibers.
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Affiliation(s)
- María S Castillo-Iglesias
- Departamento de Anatomía y Biología Celular and "Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED)", Universidad de Cantabria-IDIVAL, Avd. Cardenal Herrera Oria s/n, 39011, Santander, Spain
| | - María T Berciano
- Departamento de Biología Molecular, Universidad de Cantabria-IDIVAL, Santander, Spain
| | - J Oriol Narcis
- Departamento de Anatomía y Biología Celular and "Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED)", Universidad de Cantabria-IDIVAL, Avd. Cardenal Herrera Oria s/n, 39011, Santander, Spain
| | - J Fernando Val-Bernal
- Unidad de Patología, Departamento de Ciencias Médicas y Quirúrgicas, Universidad de Cantabria-IDIVAL, Santander, Spain
| | - José C Rodriguez-Rey
- Departamento de Biología Molecular, Universidad de Cantabria-IDIVAL, Santander, Spain
| | - Olga Tapia
- Departamento de Anatomía y Biología Celular and "Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED)", Universidad de Cantabria-IDIVAL, Avd. Cardenal Herrera Oria s/n, 39011, Santander, Spain.
| | - Miguel Lafarga
- Departamento de Anatomía y Biología Celular and "Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED)", Universidad de Cantabria-IDIVAL, Avd. Cardenal Herrera Oria s/n, 39011, Santander, Spain.
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17
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Chandran S, Suggs JA, Wang BJ, Han A, Bhide S, Cryderman DE, Moore SA, Bernstein SI, Wallrath LL, Melkani GC. Suppression of myopathic lamin mutations by muscle-specific activation of AMPK and modulation of downstream signaling. Hum Mol Genet 2019; 28:351-371. [PMID: 30239736 PMCID: PMC6337691 DOI: 10.1093/hmg/ddy332] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/11/2018] [Accepted: 09/13/2018] [Indexed: 12/14/2022] Open
Abstract
Laminopathies are diseases caused by dominant mutations in the human LMNA gene encoding A-type lamins. Lamins are intermediate filaments that line the inner nuclear membrane, provide structural support for the nucleus and regulate gene expression. Drosophila melanogaster models of skeletal muscle laminopathies were developed to investigate the pathological defects caused by mutant lamins and identify potential therapeutic targets. Human disease-causing LMNA mutations were modeled in Drosophila Lamin C (LamC) and expressed in indirect flight muscle (IFM). IFM-specific expression of mutant, but not wild-type LamC, caused held-up wings indicative of myofibrillar defects. Analyses of the muscles revealed cytoplasmic aggregates of nuclear envelope (NE) proteins, nuclear and mitochondrial dysmorphology, myofibrillar disorganization and up-regulation of the autophagy cargo receptor p62. We hypothesized that the cytoplasmic aggregates of NE proteins trigger signaling pathways that alter cellular homeostasis, causing muscle dysfunction. In support of this hypothesis, transcriptomics data from human muscle biopsy tissue revealed misregulation of the AMP-activated protein kinase (AMPK)/4E-binding protein 1 (4E-BP1)/autophagy/proteostatic pathways. Ribosomal protein S6K (S6K) messenger RNA (mRNA) levels were increased and AMPKα and mRNAs encoding downstream targets were decreased in muscles expressing mutant LMNA relative controls. The Drosophila laminopathy models were used to determine if altering the levels of these factors modulated muscle pathology. Muscle-specific over-expression of AMPKα and down-stream targets 4E-BP, Forkhead box transcription factors O (Foxo) and Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), as well as inhibition of S6K, suppressed the held-up wing phenotype, myofibrillar defects and LamC aggregation. These findings provide novel insights on mutant LMNA-based disease mechanisms and identify potential targets for drug therapy.
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Affiliation(s)
- Sahaana Chandran
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Jennifer A Suggs
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Bingyan J Wang
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Andrew Han
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Shruti Bhide
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Diane E Cryderman
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Steven A Moore
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Sanford I Bernstein
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
| | - Lori L Wallrath
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Girish C Melkani
- Department of Biology, Molecular Biology and Heart Institutes, San Diego State University, San Diego, CA, USA
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18
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Steele-Stallard HB, Pinton L, Sarcar S, Ozdemir T, Maffioletti SM, Zammit PS, Tedesco FS. Modeling Skeletal Muscle Laminopathies Using Human Induced Pluripotent Stem Cells Carrying Pathogenic LMNA Mutations. Front Physiol 2018; 9:1332. [PMID: 30405424 PMCID: PMC6201196 DOI: 10.3389/fphys.2018.01332] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 09/04/2018] [Indexed: 01/03/2023] Open
Abstract
Laminopathies are a clinically heterogeneous group of disorders caused by mutations in LMNA. The main proteins encoded by LMNA are Lamin A and C, which together with Lamin B1 and B2, form the nuclear lamina: a mesh-like structure located underneath the inner nuclear membrane. Laminopathies show striking tissue specificity, with subtypes affecting striated muscle, peripheral nerve, and adipose tissue, while others cause multisystem disease with accelerated aging. Although several pathogenic mechanisms have been proposed, the exact pathophysiology of laminopathies remains unclear, compounded by the rarity of these disorders and lack of easily accessible cell types to study. To overcome this limitation, we used induced pluripotent stem cells (iPSCs) from patients with skeletal muscle laminopathies such as LMNA-related congenital muscular dystrophy and limb-girdle muscular dystrophy 1B, to model disease phenotypes in vitro. iPSCs can be derived from readily accessible cell types, have unlimited proliferation potential and can be differentiated into cell types that would otherwise be difficult and invasive to obtain. iPSC lines from three skeletal muscle laminopathy patients were differentiated into inducible myogenic cells and myotubes. Disease-associated phenotypes were observed in these cells, including abnormal nuclear shape and mislocalization of nuclear lamina proteins. Nuclear abnormalities were less pronounced in monolayer cultures of terminally differentiated skeletal myotubes than in proliferating myogenic cells. Notably, skeletal myogenic differentiation of LMNA-mutant iPSCs in artificial muscle constructs improved detection of myonuclear abnormalities compared to conventional monolayer cultures across multiple pathogenic genotypes, providing a high-fidelity modeling platform for skeletal muscle laminopathies. Our results lay the foundation for future iPSC-based therapy development and screening platforms for skeletal muscle laminopathies.
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Affiliation(s)
- Heather B Steele-Stallard
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Luca Pinton
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Shilpita Sarcar
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Tanel Ozdemir
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Sara M Maffioletti
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Peter S Zammit
- Randall Centre for Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | - Francesco Saverio Tedesco
- Department of Cell and Developmental Biology, University College London, London, United Kingdom.,The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
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19
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Abstract
A collection of more than 30 genetic muscle diseases that share certain key features, limb-girdle muscular dystrophies are characterized by progressive weakness and muscle atrophy of the hips, shoulders, and proximal extremity muscles with postnatal onset. This article discusses clinical, laboratory, and histologic features of the 6 most prevalent limb-girdle dystrophies. In this large group of disorders, certain distinctive features often can guide clinicians to a correct diagnosis.
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20
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Müller TJ, Kraya T, Stoltenburg-Didinger G, Hanisch F, Kornhuber M, Stoevesandt D, Senderek J, Weis J, Baum P, Deschauer M, Zierz S. Phenotype of matrin-3-related distal myopathy in 16 German patients. Ann Neurol 2014; 76:669-80. [DOI: 10.1002/ana.24255] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 08/21/2014] [Accepted: 08/21/2014] [Indexed: 11/11/2022]
Affiliation(s)
- Tobias J. Müller
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Torsten Kraya
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Gisela Stoltenburg-Didinger
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
- Institute of Cell and Neurobiology; Charité University Medicine Berlin; Berlin Germany
| | - Frank Hanisch
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Malte Kornhuber
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Dietrich Stoevesandt
- Department of Diagnostic Radiology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Jan Senderek
- Friedrich Bauer Institute; Ludwig Maximilian University of Munich; Munich Germany
| | - Joachim Weis
- Institute of Neuropathology; RWTH Aachen University Hospital; Aachen Germany
| | - Petra Baum
- Clinic and Polyclinic for Neurology; University of Leipzig; Leipzig Germany
| | - Marcus Deschauer
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
| | - Stephan Zierz
- Department of Neurology; Martin Luther University of Halle-Wittenberg; Halle Germany
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21
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Congenital fiber type disproportion myopathy caused by LMNA mutations. J Neurol Sci 2014; 340:94-8. [PMID: 24642510 DOI: 10.1016/j.jns.2014.02.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/24/2014] [Accepted: 02/26/2014] [Indexed: 12/11/2022]
Abstract
A boy, who had shown muscle weakness and hypotonia from early childhood and fiber type disproportion (FTD) with no dystrophic changes on muscle biopsy, was initially diagnosed as having congenital fiber type disproportion (CFTD). Subsequently, he developed cardiac conduction blocks. We reconsidered the diagnosis as possible LMNA-myopathy and found a heterozygous mutation in the LMNA gene. This encouraged us to search for LMNA mutations on 80 patients who met the diagnostic criteria of CFTD with unknown cause. Two patients including the above index case had heterozygous in-frame deletion mutations of c.367_369delAAG and c.99_101delGGA in LMNA, respectively. Four of 23 muscular dystrophy patients with LMNA mutation also showed fiber type disproportion (FTD). Importantly, all FTD associated with LMNA-myopathy were caused by hypertrophy of type 2 fibers as compared with age-matched controls, whereas CFTD with mutations in ACTA1 or TPM3 showed selective type 1 fiber atrophy but no type 2 fiber hypertrophy. Although FTD is not a constant pathological feature of LMNA-myopathy, we should consider the possibility of LMNA-myopathy whenever a diagnosis of CFTD is made and take steps to prevent cardiac insufficiency.
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22
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Davidson PM, Lammerding J. Broken nuclei--lamins, nuclear mechanics, and disease. Trends Cell Biol 2013; 24:247-56. [PMID: 24309562 DOI: 10.1016/j.tcb.2013.11.004] [Citation(s) in RCA: 187] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 11/19/2022]
Abstract
Mutations in lamins, which are ubiquitous nuclear intermediate filaments, lead to a variety of disorders including muscular dystrophy and dilated cardiomyopathy. Lamins provide nuclear stability, help connect the nucleus to the cytoskeleton, and can modulate chromatin organization and gene expression. Nonetheless, the diverse functions of lamins remain incompletely understood. We focus here on the role of lamins on nuclear mechanics and their involvement in human diseases. Recent findings suggest that lamin mutations can decrease nuclear stability, increase nuclear fragility, and disturb mechanotransduction signaling, possibly explaining the muscle-specific defects in many laminopathies. At the same time, altered lamin expression has been reported in many cancers, where the resulting increased nuclear deformability could enhance the ability of cells to transit tight interstitial spaces, thereby promoting metastasis.
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Affiliation(s)
- Patricia M Davidson
- Weill Institute for Cell and Molecular Biology, Cornell University, 526 Campus Road, Ithaca, NY 14853, USA
| | - Jan Lammerding
- Department of Biomedical Engineering/Weill Institute for Cell and Molecular Biology, Cornell University, 526 Campus Road, Ithaca, NY 14853, USA.
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23
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Zwerger M, Jaalouk DE, Lombardi ML, Isermann P, Mauermann M, Dialynas G, Herrmann H, Wallrath LL, Lammerding J. Myopathic lamin mutations impair nuclear stability in cells and tissue and disrupt nucleo-cytoskeletal coupling. Hum Mol Genet 2013; 22:2335-49. [PMID: 23427149 DOI: 10.1093/hmg/ddt079] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Lamins are intermediate filament proteins that assemble into a meshwork underneath the inner nuclear membrane, the nuclear lamina. Mutations in the LMNA gene, encoding lamins A and C, cause a variety of diseases collectively called laminopathies. The disease mechanism for these diverse conditions is not well understood. Since lamins A and C are fundamental determinants of nuclear structure and stability, we tested whether defects in nuclear mechanics could contribute to the disease development, especially in laminopathies affecting mechanically stressed tissue such as muscle. Using skin fibroblasts from laminopathy patients and lamin A/C-deficient mouse embryonic fibroblasts stably expressing a broad panel of laminopathic lamin A mutations, we found that several mutations associated with muscular dystrophy and dilated cardiomyopathy resulted in more deformable nuclei; in contrast, lamin mutants responsible for diseases without muscular phenotypes did not alter nuclear deformability. We confirmed our results in intact muscle tissue, demonstrating that nuclei of transgenic Drosophila melanogaster muscle expressing myopathic lamin mutations deformed more under applied strain than controls. In vivo and in vitro studies indicated that the loss of nuclear stiffness resulted from impaired assembly of mutant lamins into the nuclear lamina. Although only a subset of lamin mutations associated with muscular diseases caused increased nuclear deformability, almost all mutations tested had defects in force transmission between the nucleus and cytoskeleton. In conclusion, our results indicate that although defective nuclear stability may play a role in the development of muscle diseases, other factors, such as impaired nucleo-cytoskeletal coupling, likely contribute to the muscle phenotype.
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Affiliation(s)
- Monika Zwerger
- Department of Medicine, Brigham and Women's Hospital/Harvard Medical School, Boston, MA 02115, USA
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24
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Solovei I, Wang AS, Thanisch K, Schmidt CS, Krebs S, Zwerger M, Cohen TV, Devys D, Foisner R, Peichl L, Herrmann H, Blum H, Engelkamp D, Stewart CL, Leonhardt H, Joffe B. LBR and lamin A/C sequentially tether peripheral heterochromatin and inversely regulate differentiation. Cell 2013; 152:584-98. [PMID: 23374351 DOI: 10.1016/j.cell.2013.01.009] [Citation(s) in RCA: 565] [Impact Index Per Article: 51.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 09/14/2012] [Accepted: 01/07/2013] [Indexed: 01/26/2023]
Abstract
Eukaryotic cells have a layer of heterochromatin at the nuclear periphery. To investigate mechanisms regulating chromatin distribution, we analyzed heterochromatin organization in different tissues and species, including mice with mutations in the lamin B receptor (Lbr) and lamin A (Lmna) genes that encode nuclear envelope (NE) proteins. We identified LBR- and lamin-A/C-dependent mechanisms tethering heterochromatin to the NE. The two tethers are sequentially used during cellular differentiation and development: first the LBR- and then the lamin-A/C-dependent tether. The absence of both LBR and lamin A/C leads to loss of peripheral heterochromatin and an inverted architecture with heterochromatin localizing to the nuclear interior. Myoblast transcriptome analyses indicated that selective disruption of the LBR- or lamin-A-dependent heterochromatin tethers have opposite effects on muscle gene expression, either increasing or decreasing, respectively. These results show how changes in NE composition contribute to regulating heterochromatin positioning, gene expression, and cellular differentiation during development.
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Affiliation(s)
- Irina Solovei
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
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25
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Dubinska-Magiera M, Zaremba-Czogalla M, Rzepecki R. Muscle development, regeneration and laminopathies: how lamins or lamina-associated proteins can contribute to muscle development, regeneration and disease. Cell Mol Life Sci 2012; 70:2713-41. [PMID: 23138638 PMCID: PMC3708280 DOI: 10.1007/s00018-012-1190-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 09/28/2012] [Accepted: 10/03/2012] [Indexed: 12/22/2022]
Abstract
The aim of this review article is to evaluate the current knowledge on associations between muscle formation and regeneration and components of the nuclear lamina. Lamins and their partners have become particularly intriguing objects of scientific interest since it has been observed that mutations in genes coding for these proteins lead to a wide range of diseases called laminopathies. For over the last 10 years, various laboratories worldwide have tried to explain the pathogenesis of these rare disorders. Analyses of the distinct aspects of laminopathies resulted in formulation of different hypotheses regarding the mechanisms of the development of these diseases. In the light of recent discoveries, A-type lamins—the main building blocks of the nuclear lamina—together with other key elements, such as emerin, LAP2α and nesprins, seem to be of great importance in the modulation of various signaling pathways responsible for cellular differentiation and proliferation.
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Affiliation(s)
- Magda Dubinska-Magiera
- Department of Animal Developmental Biology, University of Wroclaw, 21 Sienkiewicza Street, 50-335, Wroclaw, Poland
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26
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Lanzuolo C. Epigenetic alterations in muscular disorders. Comp Funct Genomics 2012; 2012:256892. [PMID: 22761545 PMCID: PMC3385594 DOI: 10.1155/2012/256892] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/11/2012] [Accepted: 04/19/2012] [Indexed: 11/18/2022] Open
Abstract
Epigenetic mechanisms, acting via chromatin organization, fix in time and space different transcriptional programs and contribute to the quality, stability, and heritability of cell-specific transcription programs. In the last years, great advances have been made in our understanding of mechanisms by which this occurs in normal subjects. However, only a small part of the complete picture has been revealed. Abnormal gene expression patterns are often implicated in the development of different diseases, and thus epigenetic studies from patients promise to fill an important lack of knowledge, deciphering aberrant molecular mechanisms at the basis of pathogenesis and diseases progression. The identification of epigenetic modifications that could be used as targets for therapeutic interventions could be particularly timely in the light of pharmacologically reversion of pathological perturbations, avoiding changes in DNA sequences. Here I discuss the available information on epigenetic mechanisms that, altered in neuromuscular disorders, could contribute to the progression of the disease.
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Affiliation(s)
- Chiara Lanzuolo
- CNR Institute of Cellular Biology and Neurobiology, IRCCS Santa Lucia Foundation, Via Del Fosso di Fiorano 64, 00143 Rome, Italy
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27
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Acid phosphatase-positive globular inclusions is a good diagnostic marker for two patients with adult-onset Pompe disease lacking disease specific pathology. Neuromuscul Disord 2012; 22:389-93. [DOI: 10.1016/j.nmd.2011.11.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 10/19/2011] [Accepted: 11/15/2011] [Indexed: 11/21/2022]
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28
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Puckelwartz MJ, Depreux FF, McNally EM. Gene expression, chromosome position and lamin A/C mutations. Nucleus 2012; 2:162-7. [PMID: 21818408 DOI: 10.4161/nucl.2.3.16003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 04/22/2011] [Accepted: 04/26/2011] [Indexed: 12/11/2022] Open
Abstract
The nuclear lamina is increasingly being appreciated for its epigenetic role in regulating gene expression. The nuclear lamina underlies the inner nuclear membrane and, in post mitotic cells, is composed of a latticework primarily formed by the intermediate filament protein, lamin A/C. Although not well defined, lamin-associated domains have been described, and these domains are determined by DNA sequence and chromatin conformation. Lamin-associated domains are positioned to mediate the interaction with the nuclear membrane, where they contribute to transcriptional regulation. Although lamin-associated domains are primarily considered to be repressive in nature, those nearer to nuclear pores may actually promote transcription. Mutations in LMNA, the gene encoding lamins A and C, are a relatively common cause of inherited cardiomyopathy. As substantial data supports a role for the lamina in its interaction with chromatin and gene regulation, we examined the role of a genetically disrupted lamina and the consequences thereof. A dominant LMNA mutation, E161K, that causes inherited cardiomyopathy was studied. Gene expression changes were profiled in a human cardiomyopathic E161K heart, and it was found that chromosome 13 had a high percentage of misexpressed genes. Chromosome 13 was also found to be less tightly associated with the nuclear membrane in E161K mutant cells, thereby linking abnormal gene expression and intranuclear position. These and other studies support a role for the nuclear membrane as an active regulator of gene expression and provide additional support that disrupting this regulation is a mechanism of human disease.
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29
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Komaki H, Hayashi YK, Tsuburaya R, Sugie K, Kato M, Nagai T, Imataka G, Suzuki S, Saitoh S, Asahina N, Honke K, Higuchi Y, Sakuma H, Saito Y, Nakagawa E, Sugai K, Sasaki M, Nonaka I, Nishino I. Inflammatory changes in infantile-onset LMNA-associated myopathy. Neuromuscul Disord 2011; 21:563-8. [PMID: 21632249 DOI: 10.1016/j.nmd.2011.04.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 04/12/2011] [Accepted: 04/20/2011] [Indexed: 01/29/2023]
Abstract
Mutations in LMNA cause wide variety of disorders including Emery-Dreifuss muscular dystrophy, limb girdle muscular dystrophy, and congenital muscular dystrophy. We recently found a LMNA mutation in a patient who was previously diagnosed as infantile onset inflammatory myopathy. In this study, we screened for LMNA mutations in 20 patients suspected to have inflammatory myopathy with onset at 2years or younger. The diagnosis of inflammatory myopathy was based on muscle pathology with presence of perivascular cuffing and/or endomysial/perimysial lymphocyte infiltration. We identified heterozygous LMNA mutations in 11 patients (55%), who eventually developed joint contractures and/or cardiac involvement after the infantile period. Our findings suggest that LMNA mutation should be considered in myopathy patients with inflammatory changes during infancy, and that this may help avoid life-threatening events associated with laminopathy.
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Affiliation(s)
- Hirofumi Komaki
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry (NCNP), Ogawa-Higashi, Kodaira, Tokyo, Japan
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30
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Gnocchi VF, Scharner J, Huang Z, Brady K, Lee JS, White RB, Morgan JE, Sun YB, Ellis JA, Zammit PS. Uncoordinated transcription and compromised muscle function in the lmna-null mouse model of Emery- Emery-Dreyfuss muscular dystrophy. PLoS One 2011; 6:e16651. [PMID: 21364987 PMCID: PMC3043058 DOI: 10.1371/journal.pone.0016651] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 12/23/2010] [Indexed: 12/15/2022] Open
Abstract
LMNA encodes both lamin A and C: major components of the nuclear lamina. Mutations in LMNA underlie a range of tissue-specific degenerative diseases, including those that affect skeletal muscle, such as autosomal-Emery-Dreifuss muscular dystrophy (A-EDMD) and limb girdle muscular dystrophy 1B. Here, we examine the morphology and transcriptional activity of myonuclei, the structure of the myotendinous junction and the muscle contraction dynamics in the lmna-null mouse model of A-EDMD. We found that there were fewer myonuclei in lmna-null mice, of which ∼50% had morphological abnormalities. Assaying transcriptional activity by examining acetylated histone H3 and PABPN1 levels indicated that there was a lack of coordinated transcription between myonuclei lacking lamin A/C. Myonuclei with abnormal morphology and transcriptional activity were distributed along the length of the myofibre, but accumulated at the myotendinous junction. Indeed, in addition to the presence of abnormal myonuclei, the structure of the myotendinous junction was perturbed, with disorganised sarcomeres and reduced interdigitation with the tendon, together with lipid and collagen deposition. Functionally, muscle contraction became severely affected within weeks of birth, with specific force generation dropping as low as ∼65% and ∼27% of control values in the extensor digitorum longus and soleus muscles respectively. These observations illustrate the importance of lamin A/C for correct myonuclear function, which likely acts synergistically with myotendinous junction disorganisation in the development of A-EDMD, and the consequential reduction in force generation and muscle wasting.
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MESH Headings
- Animals
- Cell Nucleus/metabolism
- Cell Nucleus/pathology
- Cell Nucleus/physiology
- Chromatin Assembly and Disassembly/genetics
- Chromatin Assembly and Disassembly/physiology
- Disease Models, Animal
- Growth and Development/genetics
- Intercellular Junctions/metabolism
- Intercellular Junctions/pathology
- Intercellular Junctions/ultrastructure
- Lamin Type A/genetics
- Lamin Type A/metabolism
- Lamin Type A/physiology
- Mice
- Mice, Knockout
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Skeletal/pathology
- Muscle Fibers, Skeletal/physiology
- Muscle Fibers, Skeletal/ultrastructure
- Muscle Weakness/genetics
- Muscle Weakness/pathology
- Muscles/metabolism
- Muscles/pathology
- Muscles/physiopathology
- Muscular Dystrophy, Emery-Dreifuss/genetics
- Muscular Dystrophy, Emery-Dreifuss/metabolism
- Muscular Dystrophy, Emery-Dreifuss/pathology
- Muscular Dystrophy, Emery-Dreifuss/physiopathology
- RNA Processing, Post-Transcriptional/genetics
- RNA Processing, Post-Transcriptional/physiology
- Transcription, Genetic/physiology
- Weight Loss/genetics
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Affiliation(s)
- Viola F. Gnocchi
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Juergen Scharner
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Zhe Huang
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Ken Brady
- Centre for Ultrastructural Imaging, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Jaclyn S. Lee
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Robert B. White
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Jennifer E. Morgan
- The Dubowitz Neuromuscular Centre, Institute of Child Health, University College, London, United Kingdom
| | - Yin-Biao Sun
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Juliet A. Ellis
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
| | - Peter S. Zammit
- The Randall Division of Cell and Molecular Biophysics, King's College London, New Hunt's House, Guy's Campus, London, United Kingdom
- * E-mail:
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31
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Laminopathies: the molecular background of the disease and the prospects for its treatment. Cell Mol Biol Lett 2010; 16:114-48. [PMID: 21225470 PMCID: PMC6275778 DOI: 10.2478/s11658-010-0038-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 12/13/2010] [Indexed: 02/06/2023] Open
Abstract
Laminopathies are rare human degenerative disorders with a wide spectrum of clinical phenotypes, associated with defects in the main protein components of the nuclear envelope, mostly in the lamins. They include systemic disorders and tissue-restricted diseases. Scientists have been trying to explain the pathogenesis of laminopathies and find an efficient method for treatment for many years. In this review, we discuss the current state of knowledge about laminopathies, the molecular mechanisms behind the development of particular phenotypes, and the prospects for stem cell and/or gene therapy treatments.
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32
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Mitsuhashi H, Hayashi YK, Matsuda C, Noguchi S, Wakatsuki S, Araki T, Nishino I. Specific phosphorylation of Ser458 of A-type lamins in LMNA-associated myopathy patients. J Cell Sci 2010; 123:3893-900. [DOI: 10.1242/jcs.072157] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mutations in LMNA, which encodes A-type nuclear lamins, cause various human diseases, including myopathy, cardiomyopathy, lipodystrophy and progeria syndrome. To date, little is known about how mutations in a single gene cause a wide variety of diseases. Here, by characterizing an antibody that specifically recognizes the phosphorylation of Ser458 of A-type lamins, we uncover findings that might contribute to our understanding of laminopathies. This antibody only reacts with nuclei in muscle biopsies from myopathy patients with mutations in the Ig-fold motif of A-type lamins. Ser458 phosphorylation is not seen in muscles from control patients or patients with any other neuromuscular diseases. In vitro analysis confirmed that only lamin A mutants associated with myopathy induce phosphorylation of Ser458, whereas lipodystrophy- or progeria-associated mutants do not. We also found that Akt1 directly phosphorylates Ser458 of lamin A with myopathy-related mutations in vitro. These results suggest that Ser458 phosphorylation of A-type lamins correlates with striated muscle laminopathies; this might be useful for the early diagnosis of LMNA-associated myopathies. We propose that disease-specific phosphorylation of A-type lamins by Akt1 contributes to myopathy caused by LMNA mutations.
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Affiliation(s)
- Hiroaki Mitsuhashi
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8502, Japan
| | - Yukiko K. Hayashi
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8502, Japan
| | - Chie Matsuda
- Neuroscience Research Institute, AIST, Central 6, Tsukuba, Ibaraki 305-8566, Japan
| | - Satoru Noguchi
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8502, Japan
| | - Shuji Wakatsuki
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan
| | - Toshiyuki Araki
- Department of Peripheral Nervous System Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8502, Japan
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33
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Muscular laminopathies: role of prelamin A in early steps of muscle differentiation. ACTA ACUST UNITED AC 2010; 51:246-56. [PMID: 21035482 DOI: 10.1016/j.advenzreg.2010.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 09/14/2010] [Indexed: 11/23/2022]
Abstract
Lamin A is a nuclear envelope constituent involved in a group of human disorders, collectively referred to as laminopathies, which include Emery-Dreifuss muscular dystrophy. Because increasing evidence suggests a role of lamin A precursor in nuclear functions, we investigated the processing of prelamin A along muscle differentiation. Both protein levels and cellular localization of prelamin A appears to be modulated during C2C12 mouse myoblasts activation. Similar changes also occur in the expression of two lamin A-binding proteins: emerin and LAP2α. Furthermore prelamin A forms a complex with LAP2α in differentiating myoblasts. Prelamin A accumulation in cycling myoblasts by expressing unprocessable mutants affects LAP2α and PCNA amount and increases caveolin 3 mRNA and protein levels, whilst accumulation of prelamin A in differentiated muscle cells following treatment with a farnesyl transferase inhibitor inhibits caveolin 3 expression. These data provide evidence for a critical role of lamin A precursor in the early steps of muscle cell differentiation. In fact the post-translational processing of prelamin A affects caveolin 3 expression and influences the myoblast differentiation process. Thus, altered lamin A processing could affect myoblast differentiation and/or muscle regeneration and might contribute to the myopathic phenotype.
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34
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A molecular mechanism underlying the neural-specific defect in torsinA mutant mice. Proc Natl Acad Sci U S A 2010; 107:9861-6. [PMID: 20457914 DOI: 10.1073/pnas.0912877107] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A striking but poorly understood feature of many diseases is the unique involvement of neural tissue. One example is the CNS-specific disorder DYT1 dystonia, caused by a 3-bp deletion ("DeltaE") in the widely expressed gene TOR1A. Disease mutant knockin mice (Tor1a(DeltaE/DeltaE)) exhibit disrupted nuclear membranes selectively in neurons, mimicking the tissue specificity of the human disease and providing a model system in which to dissect the mechanisms underlying neural selectivity. Our in vivo studies demonstrate that lamina-associated polypeptide 1 (LAP1) and torsinB function with torsinA to maintain normal nuclear membrane morphology. Moreover, we show that nonneuronal cells express dramatically higher levels of torsinB and that RNAi-mediated depletion of torsinB (but not other torsin family members) causes nuclear membrane abnormalities in Tor1a(DeltaE/DeltaE) nonneuronal cells. The Tor1a(DeltaE/DeltaE) neural selective phenotype therefore arises because high levels of torsinB protect nonneuronal cells from the consequences of torsinA dysfunction, demonstrating how tissue specificity may result from differential susceptibility of cell types to insults that disrupt ubiquitous biological pathways.
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35
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Abstract
A- and B-type lamins are the major intermediate filaments of the nucleus. Lamins engage in a plethora of stable and transient interactions, near the inner nuclear membrane and throughout the nucleus. Lamin-binding proteins serve an amazingly diverse range of functions. Numerous inner-membrane proteins help anchor lamin filaments to the nuclear envelope, serving as part of the nuclear "lamina" network that is essential for nuclear architecture and integrity. Certain lamin-binding proteins of the inner membrane bind partners in the outer membrane and mechanically link lamins to the cytoskeleton. Inside the nucleus, lamin-binding proteins appear to serve as the "adaptors" by which the lamina organizes chromatin, influences gene expression and epigenetic regulation, and modulates signaling pathways. Transient interactions of lamins with key components of the transcription and replication machinery may provide an additional level of regulation or support to these essential events.
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Affiliation(s)
- Katherine L Wilson
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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36
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Andrés V, González JM. Role of A-type lamins in signaling, transcription, and chromatin organization. ACTA ACUST UNITED AC 2010; 187:945-57. [PMID: 20038676 PMCID: PMC2806284 DOI: 10.1083/jcb.200904124] [Citation(s) in RCA: 214] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A-type lamins (lamins A and C), encoded by the LMNA gene, are major protein constituents of the mammalian nuclear lamina, a complex structure that acts as a scaffold for protein complexes that regulate nuclear structure and functions. Interest in these proteins has increased in recent years with the discovery that LMNA mutations cause a variety of human diseases termed laminopathies, including progeroid syndromes and disorders that primarily affect striated muscle, adipose, bone, and neuronal tissues. In this review, we discuss recent research supporting the concept that lamin A/C and associated nuclear envelope proteins regulate gene expression in health and disease through interplay with signal transduction pathways, transcription factors, and chromatin-associated proteins.
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Affiliation(s)
- Vicente Andrés
- Department of Atherothrombosis and Cardiovascular Imaging, Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain.
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37
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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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Wallace DC, Fan W. Energetics, epigenetics, mitochondrial genetics. Mitochondrion 2009; 10:12-31. [PMID: 19796712 DOI: 10.1016/j.mito.2009.09.006] [Citation(s) in RCA: 351] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2009] [Revised: 09/21/2009] [Accepted: 09/23/2009] [Indexed: 12/15/2022]
Abstract
The epigenome has been hypothesized to provide the interface between the environment and the nuclear DNA (nDNA) genes. Key factors in the environment are the availability of calories and demands on the organism's energetic capacity. Energy is funneled through glycolysis and mitochondrial oxidative phosphorylation (OXPHOS), the cellular bioenergetic systems. Since there are thousands of bioenergetic genes dispersed across the chromosomes and mitochondrial DNA (mtDNA), both cis and trans regulation of the nDNA genes is required. The bioenergetic systems convert environmental calories into ATP, acetyl-Coenzyme A (acetyl-CoA), s-adenosyl-methionine (SAM), and reduced NAD(+). When calories are abundant, ATP and acetyl-CoA phosphorylate and acetylate chromatin, opening the nDNA for transcription and replication. When calories are limiting, chromatin phosphorylation and acetylation are lost and gene expression is suppressed. DNA methylation via SAM can also be modulated by mitochondrial function. Phosphorylation and acetylation are also pivotal to regulating cellular signal transduction pathways. Therefore, bioenergetics provides the interface between the environment and the epigenome. Consistent with this conclusion, the clinical phenotypes of bioenergetic diseases are strikingly similar to those observed in epigenetic diseases (Angelman, Rett, Fragile X Syndromes, the laminopathies, cancer, etc.), and an increasing number of epigenetic diseases are being associated with mitochondrial dysfunction. This bioenergetic-epigenomic hypothesis has broad implications for the etiology, pathophysiology, and treatment of a wide range of common diseases.
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Affiliation(s)
- Douglas C Wallace
- Center for Molecular and Mitochondrial Medicine and Genetics (MAMMAG), University of California, Irvine, CA 92697-3940, USA.
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Further characterisation of the molecular signature of quiescent and activated mouse muscle satellite cells. PLoS One 2009; 4:e5205. [PMID: 19370151 PMCID: PMC2666265 DOI: 10.1371/journal.pone.0005205] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Accepted: 03/12/2009] [Indexed: 11/19/2022] Open
Abstract
Satellite cells are the resident stem cells of adult skeletal muscle. To date though, there is a paucity of native markers that can be used to easily identify quiescent satellite cells, with Pax7 probably being the best that is currently available. Here we have further characterized a number of recently described satellite cell markers, and also describe novel ones. Caveolin-1, integrin α7 and the calcitonin receptor proved reliable markers for quiescent satellite cells, being expressed by all satellite cells identified with Pax7. These three markers remained expressed as satellite cells were activated and underwent proliferation. The nuclear envelope proteins lamin A/C and emerin, mutations in which underlie Emery-Dreifuss muscular dystrophy, were also expressed in both quiescent and proliferating satellite cells. Conversely, Jagged-1, a Notch ligand, was not expressed in quiescent satellite cells but was induced upon activation. These findings further contribute to defining the molecular signature of muscle satellite cells.
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