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Feng L, Chen Z, Bian H. Skeletal muscle: molecular structure, myogenesis, biological functions, and diseases. MedComm (Beijing) 2024; 5:e649. [PMID: 38988494 PMCID: PMC11234433 DOI: 10.1002/mco2.649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 06/13/2024] [Accepted: 06/17/2024] [Indexed: 07/12/2024] Open
Abstract
Skeletal muscle is an important motor organ with multinucleated myofibers as its smallest cellular units. Myofibers are formed after undergoing cell differentiation, cell-cell fusion, myonuclei migration, and myofibril crosslinking among other processes and undergo morphological and functional changes or lesions after being stimulated by internal or external factors. The above processes are collectively referred to as myogenesis. After myofibers mature, the function and behavior of skeletal muscle are closely related to the voluntary movement of the body. In this review, we systematically and comprehensively discuss the physiological and pathological processes associated with skeletal muscles from five perspectives: molecule basis, myogenesis, biological function, adaptive changes, and myopathy. In the molecular structure and myogenesis sections, we gave a brief overview, focusing on skeletal muscle-specific fusogens and nuclei-related behaviors including cell-cell fusion and myonuclei localization. Subsequently, we discussed the three biological functions of skeletal muscle (muscle contraction, thermogenesis, and myokines secretion) and its response to stimulation (atrophy, hypertrophy, and regeneration), and finally settled on myopathy. In general, the integration of these contents provides a holistic perspective, which helps to further elucidate the structure, characteristics, and functions of skeletal muscle.
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Affiliation(s)
- Lan‐Ting Feng
- Department of Cell Biology & National Translational Science Center for Molecular MedicineNational Key Laboratory of New Drug Discovery and Development for Major DiseasesFourth Military Medical UniversityXi'anChina
| | - Zhi‐Nan Chen
- Department of Cell Biology & National Translational Science Center for Molecular MedicineNational Key Laboratory of New Drug Discovery and Development for Major DiseasesFourth Military Medical UniversityXi'anChina
| | - Huijie Bian
- Department of Cell Biology & National Translational Science Center for Molecular MedicineNational Key Laboratory of New Drug Discovery and Development for Major DiseasesFourth Military Medical UniversityXi'anChina
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2
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Dugdale HF, Levy Y, Jungbluth H, Oldfors A, Ochala J. Aberrant myonuclear domains and impaired myofiber contractility despite marked hypertrophy in MYMK-related, Carey-Fineman-Ziter Syndrome. Acta Neuropathol Commun 2024; 12:80. [PMID: 38790073 PMCID: PMC11127446 DOI: 10.1186/s40478-024-01783-2] [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: 02/09/2024] [Accepted: 04/10/2024] [Indexed: 05/26/2024] Open
Abstract
Carey Fineman Ziter Syndrome (CFZS) is a rare autosomal recessive disease caused by mutations in the MYMK locus which encodes the protein, myomaker. Myomaker is essential for fusion and concurrent myonuclei donation of muscle progenitors during growth and development. Strikingly, in humans, MYMK mutations appear to prompt myofiber hypertrophy but paradoxically, induce generalised muscle weakness. As the underlying cellular mechanisms remain unexplored, the present study aimed to gain insights by combining myofiber deep-phenotyping and proteomic profiling. Hence, we isolated individual muscle fibers from CFZS patients and performed mechanical, 3D morphological and proteomic analyses. Myofibers from CFZS patients were ~ 4x larger than controls and possessed ~ 2x more myonuclei than those from healthy subjects, leading to disproportionally larger myonuclear domain volumes. These greater myonuclear domain sizes were accompanied by smaller intrinsic cellular force generating-capacities in myofibers from CFZS patients than in control muscle cells. Our complementary proteomic analyses indicated remodelling in 233 proteins particularly those associated with cellular respiration. Overall, our findings suggest that myomaker is somewhat functional in CFZS patients, but the associated nuclear accretion may ultimately lead to non-functional hypertrophy and altered energy-related mechanisms in CFZS patients. All of these are likely contributors of the muscle weakness experienced by CFZS patients.
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Affiliation(s)
- Hannah F Dugdale
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Yotam Levy
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Heinz Jungbluth
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and Medicine (FoLSM), King's College London, London, UK
- Department of Paediatric Neurology, Neuromuscular Service, Evelina Children's Hospital, Guy's and St Thomas' Hospital NHS Foundation Trust, London, UK
| | - Anders Oldfors
- Department of Laboratory Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Julien Ochala
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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3
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Rocha AL, Pai V, Perkins G, Chang T, Ma J, De Souza EV, Chu Q, Vaughan JM, Diedrich JK, Ellisman MH, Saghatelian A. An Inner Mitochondrial Membrane Microprotein from the SLC35A4 Upstream ORF Regulates Cellular Metabolism. J Mol Biol 2024; 436:168559. [PMID: 38580077 DOI: 10.1016/j.jmb.2024.168559] [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: 01/21/2024] [Revised: 03/29/2024] [Accepted: 03/31/2024] [Indexed: 04/07/2024]
Abstract
Upstream open reading frames (uORFs) are cis-acting elements that can dynamically regulate the translation of downstream ORFs by suppressing downstream translation under basal conditions and, in some cases, increasing downstream translation under stress conditions. Computational and empirical methods have identified uORFs in the 5'-UTRs of approximately half of all mouse and human transcripts, making uORFs one of the largest regulatory elements known. Because the prevailing dogma was that eukaryotic mRNAs produce a single functional protein, the peptides and small proteins, or microproteins, encoded by uORFs were rarely studied. We hypothesized that a uORF in the SLC35A4 mRNA is producing a functional microprotein (SLC35A4-MP) because of its conserved amino acid sequence. Through a series of biochemical and cellular experiments, we find that the 103-amino acid SLC35A4-MP is a single-pass transmembrane inner mitochondrial membrane (IMM) microprotein. The IMM contains the protein machinery crucial for cellular respiration and ATP generation, and loss of function studies with SLC35A4-MP significantly diminish maximal cellular respiration, indicating a vital role for this microprotein in cellular metabolism. The findings add SLC35A4-MP to the growing list of functional microproteins and, more generally, indicate that uORFs that encode conserved microproteins are an untapped reservoir of functional microproteins.
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Affiliation(s)
- Andréa L Rocha
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Victor Pai
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Guy Perkins
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Tina Chang
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Jiao Ma
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Eduardo V De Souza
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Qian Chu
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Joan M Vaughan
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Jolene K Diedrich
- Mass Spectrometry Core for Proteomics and Metabolomics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA, USA.
| | - Alan Saghatelian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA, USA.
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4
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Higashihara T, Odawara M, Nishi H, Sugasawa T, Suzuki Y, Kametaka S, Inagi R, Nangaku M. Uremia Impedes Skeletal Myocyte Myomixer Expression and Fusogenic Activity: Implication for Uremic Sarcopenia. THE AMERICAN JOURNAL OF PATHOLOGY 2024; 194:759-771. [PMID: 38637109 DOI: 10.1016/j.ajpath.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 12/10/2023] [Accepted: 01/10/2024] [Indexed: 04/20/2024]
Abstract
In patients with chronic kidney disease (CKD), skeletal muscle mass and function are known to occasionally decline. However, the muscle regeneration and differentiation process in uremia has not been extensively studied. In mice with CKD induced by adenine-containing diet, the tibialis anterior muscle injured using a barium chloride injection method recovered poorly as compared to control mice. In the cultured murine skeletal myocytes, stimulation with indoxyl sulfate (IS), a representative uremic toxin, morphologically jeopardized the differentiation, which was counteracted by L-ascorbic acid (L-AsA) treatment. Transcriptome analysis of cultured myocytes identified a set of genes whose expression was down-regulated by IS stimulation but up-regulated by L-AsA treatment. Gene silencing of myomixer, one of the genes in the set, impaired myocyte fusion during differentiation. By contrast, lentiviral overexpression of myomixer compensated for a hypomorphic phenotype caused by IS treatment. The split-luciferase technique demonstrated that IS stimulation negatively affected early myofusion activity that was rescued by L-AsA treatment. Lastly, in mice with CKD compared with control mice, myomixer expression in the muscle tissue in addition to the muscle weight after the injury was reduced, both of which were restored with L-AsA treatment. Collectively, data showed that the uremic milieu impairs the expression of myomixer and impedes the myofusion process. Considering frequent musculoskeletal injuries in uremic patients, defective myocyte fusion followed by delayed muscle damage recovery could underlie their muscle loss and weakness.
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Affiliation(s)
- Takaaki Higashihara
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Motoki Odawara
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Hiroshi Nishi
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
| | - Takehito Sugasawa
- Laboratory of Clinical Examination/Sports Medicine, Department of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; Department of Sports Medicine Analysis, Open Facility Network Office, Research Facility Center for Science and Technology, University of Tsukuba, Ibaraki, Japan
| | - Yumika Suzuki
- Division of Biofunctional Sciences, Department of Integrated Health Sciences, Graduate School of Medicine, Nagoya University, Aichi, Japan
| | - Satoshi Kametaka
- Division of Biofunctional Sciences, Department of Integrated Health Sciences, Graduate School of Medicine, Nagoya University, Aichi, Japan
| | - Reiko Inagi
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
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Wherley TJ, Thomas S, Millay DP, Saunders T, Roy S. Molecular regulation of myocyte fusion. Curr Top Dev Biol 2024; 158:53-82. [PMID: 38670716 DOI: 10.1016/bs.ctdb.2024.01.016] [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] [Indexed: 04/28/2024]
Abstract
Myocyte fusion is a pivotal process in the development and regeneration of skeletal muscle. Failure during fusion can lead to a range of developmental as well as pathological consequences. This review aims to comprehensively explore the intricate processes underlying myocyte fusion, from the molecular to tissue scale. We shed light on key players, such as the muscle-specific fusogens - Myomaker and Myomixer, in addition to some lesser studied molecules contributing to myocyte fusion. Conserved across vertebrates, Myomaker and Myomixer play a crucial role in driving the merger of plasma membranes of fusing myocytes, ensuring the formation of functional muscle syncytia. Our multiscale approach also delves into broader cell and tissue dynamics that orchestrate the timing and positioning of fusion events. In addition, we explore the relevance of muscle fusogens to human health and disease. Mutations in fusogen genes have been linked to congenital myopathies, providing unique insights into the molecular basis of muscle diseases. We conclude with a discussion on potential therapeutic avenues that may emerge from manipulating the myocyte fusion process to remediate skeletal muscle disorders.
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Affiliation(s)
- Tanner J Wherley
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Serena Thomas
- Warwick Medical School, University of Warwick, Coventry, United Kingdom; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore, Singapore
| | - Douglas P Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States.
| | - Timothy Saunders
- Warwick Medical School, University of Warwick, Coventry, United Kingdom; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore, Singapore.
| | - Sudipto Roy
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore, Singapore; Department of Pediatrics, National University of Singapore, Singapore, Singapore.
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6
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Xie L, Bowman ME, Louie GV, Zhang C, Ardejani MS, Huang X, Chu Q, Donaldson CJ, Vaughan JM, Shan H, Powers ET, Kelly JW, Lyumkis D, Noel JP, Saghatelian A. Biochemistry and Protein Interactions of the CYREN Microprotein. Biochemistry 2023; 62:3050-3060. [PMID: 37813856 DOI: 10.1021/acs.biochem.3c00397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
Over the past decade, advances in genomics have identified thousands of additional protein-coding small open reading frames (smORFs) missed by traditional gene finding approaches. These smORFs encode peptides and small proteins, commonly termed micropeptides or microproteins. Several of these newly discovered microproteins have biological functions and operate through interactions with proteins and protein complexes within the cell. CYREN1 is a characterized microprotein that regulates double-strand break repair in mammalian cells through interaction with Ku70/80 heterodimer. Ku70/80 binds to and stabilizes double-strand breaks and recruits the machinery needed for nonhomologous end join repair. In this study, we examined the biochemical properties of CYREN1 to better understand and explain its cellular protein interactions. Our findings support that CYREN1 is an intrinsically disordered microprotein and this disordered structure allows it to enriches several proteins, including a newly discovered interaction with SF3B1 via a distinct short linear motif (SLiMs) on CYREN1. Since many microproteins are predicted to be disordered, CYREN1 is an exemplar of how microproteins interact with other proteins and reveals an unknown scaffolding function of this microprotein that may link NHEJ and splicing.
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Affiliation(s)
- Lina Xie
- Clayton Foundation Peptide Biology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Marianne E Bowman
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Gordon V Louie
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Cheng Zhang
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Maziar S Ardejani
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Xuemei Huang
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92037, United States
| | - Qian Chu
- Department of Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Cynthia J Donaldson
- Clayton Foundation Peptide Biology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Joan M Vaughan
- Clayton Foundation Peptide Biology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Huanqi Shan
- Clayton Foundation Peptide Biology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Evan T Powers
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Jeffery W Kelly
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Dimitry Lyumkis
- Laboratory of Genetics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Joseph P Noel
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Alan Saghatelian
- Clayton Foundation Peptide Biology Laboratories, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, United States
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Long T, Zhang Y, Donnelly L, Li H, Pien YC, Liu N, Olson EN, Li X. Cryo-EM structures of Myomaker reveal a molecular basis for myoblast fusion. Nat Struct Mol Biol 2023; 30:1746-1754. [PMID: 37770716 DOI: 10.1038/s41594-023-01110-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 08/25/2023] [Indexed: 09/30/2023]
Abstract
The fusion of mononucleated myoblasts produces multinucleated muscle fibers leading to the formation of skeletal muscle. Myomaker, a skeletal muscle-specific membrane protein, is essential for myoblast fusion. Here we report the cryo-EM structures of mouse Myomaker (mMymk) and Ciona robusta Myomaker (cMymk). Myomaker contains seven transmembrane helices (TMs) that adopt a G-protein-coupled receptor-like fold. TMs 2-4 form a dimeric interface, while TMs 3 and 5-7 create a lipid-binding site that holds the polar head of a phospholipid and allows the alkyl tails to insert into Myomaker. The similarity of cMymk and mMymk suggests a conserved Myomaker-mediated cell fusion mechanism across evolutionarily distant species. Functional analyses demonstrate the essentiality of the dimeric interface and the lipid-binding site for fusogenic activity, and heterologous cell-cell fusion assays show the importance of transcellular interactions of Myomaker protomers for myoblast fusion. Together, our findings provide structural and functional insights into the process of myoblast fusion.
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Affiliation(s)
- Tao Long
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yichi Zhang
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Linda Donnelly
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Hui Li
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yu-Chung Pien
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ning Liu
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Eric N Olson
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Xiaochun Li
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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Li K, Li B, Zhang D, Du T, Zhou H, Dai G, Yan Y, Gao N, Zhuang X, Liao X, Liu C, Dong Y, Chen D, Qu LH, Ou J, Yang JH, Huang ZP. The translational landscape of human vascular smooth muscle cells identifies novel short open reading frame-encoded peptide regulators for phenotype alteration. Cardiovasc Res 2023; 119:1763-1779. [PMID: 36943764 DOI: 10.1093/cvr/cvad044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 01/09/2023] [Accepted: 01/19/2023] [Indexed: 03/23/2023] Open
Abstract
AIMS The plasticity of vascular smooth muscle cells (VSMCs) enables them to alter phenotypes under various physiological and pathological stimuli. The alteration of VSMC phenotype is a key step in vascular diseases, including atherosclerosis. Although the transcriptome shift during VSMC phenotype alteration has been intensively investigated, uncovering multiple key regulatory signalling pathways, the translatome dynamics in this cellular process, remain largely unknown. Here, we explored the genome-wide regulation at the translational level of human VSMCs during phenotype alteration. METHODS AND RESULTS We generated nucleotide-resolution translatome and transcriptome data from human VSMCs undergoing phenotype alteration. Deep sequencing of ribosome-protected fragments (Ribo-seq) revealed alterations in protein synthesis independent of changes in messenger ribonucleicacid levels. Increased translational efficiency of many translational machinery components, including ribosomal proteins, eukaryotic translation elongation factors and initiation factors were observed during the phenotype alteration of VSMCs. In addition, hundreds of candidates for short open reading frame-encoded polypeptides (SEPs), a class of peptides containing 200 amino acids or less, were identified in a combined analysis of translatome and transcriptome data with a high positive rate in validating their coding capability. Three evolutionarily conserved SEPs were further detected endogenously by customized antibodies and suggested to participate in the pathogenesis of atherosclerosis by analysing the transcriptome and single cell RNA-seq data from patient atherosclerotic artery samples. Gain- and loss-of-function studies in human VSMCs and genetically engineered mice showed that these SEPs modulate the alteration of VSMC phenotype through different signalling pathways, including the mitogen-activated protein kinase pathway and p53 pathway. CONCLUSION Our study indicates that an increase in the capacity of translation, which is attributable to an increased quantity of translational machinery components, mainly controls alterations of VSMC phenotype at the level of translational regulation. In addition, SEPs could function as important regulators in the phenotype alteration of human VSMCs.
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Affiliation(s)
- Kang Li
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Bin Li
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-sen University, 135 Xingang Xi Road, Guangzhou 510275, China
| | - Dihua Zhang
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Tailai Du
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Huimin Zhou
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Gang Dai
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Youchen Yan
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Nailin Gao
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Xiaodong Zhuang
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Xinxue Liao
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Chen Liu
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Yugang Dong
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Demeng Chen
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Liang-Hu Qu
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-sen University, 135 Xingang Xi Road, Guangzhou 510275, China
| | - Jingsong Ou
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
- National-Guangdong Joint Engineering Laboratory for Diagnosis and Treatment of Vascular Diseases (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
| | - Jian-Hua Yang
- Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-sen University, 135 Xingang Xi Road, Guangzhou 510275, China
| | - Zhan-Peng Huang
- 1Department of Cardiology, Center for Translational Medicine, Institute of Precision Medicine, The First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Er Road, Guangzhou 510080, China
- NHC Key Laboratory of Assisted Circulation (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
- National-Guangdong Joint Engineering Laboratory for Diagnosis and Treatment of Vascular Diseases (Sun Yat-sen University), 58 Zhongshan Er Road, Guangzhou 510080, China
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9
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Tran V, Nahlé S, Robert A, Desanlis I, Killoran R, Ehresmann S, Thibault MP, Barford D, Ravichandran KS, Sauvageau M, Smith MJ, Kmita M, Côté JF. Biasing the conformation of ELMO2 reveals that myoblast fusion can be exploited to improve muscle regeneration. Nat Commun 2022; 13:7077. [PMID: 36400788 PMCID: PMC9674853 DOI: 10.1038/s41467-022-34806-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 11/08/2022] [Indexed: 11/21/2022] Open
Abstract
Myoblast fusion is fundamental for the development of multinucleated myofibers. Evolutionarily conserved proteins required for myoblast fusion include RAC1 and its activator DOCK1. In the current study we analyzed the contribution of the DOCK1-interacting ELMO scaffold proteins to myoblast fusion. When Elmo1-/- mice underwent muscle-specific Elmo2 genetic ablation, they exhibited severe myoblast fusion defects. A mutation in the Elmo2 gene that reduced signaling resulted in a decrease in myoblast fusion. Conversely, a mutation in Elmo2 coding for a protein with an open conformation increased myoblast fusion during development and in muscle regeneration. Finally, we showed that the dystrophic features of the Dysferlin-null mice, a model of limb-girdle muscular dystrophy type 2B, were reversed when expressing ELMO2 in an open conformation. These data provide direct evidence that the myoblast fusion process could be exploited for regenerative purposes and improve the outcome of muscle diseases.
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Affiliation(s)
- Viviane Tran
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada
| | - Sarah Nahlé
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Molecular Biology Programs, Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Amélie Robert
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
| | - Inès Desanlis
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Department of Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada
| | - Ryan Killoran
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC, H3T 1J4, Canada
| | - Sophie Ehresmann
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Molecular Biology Programs, Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | | | - David Barford
- MRC Laboratory of Molecular Biology, Cambridge, CB2 OQH, UK
| | - Kodi S Ravichandran
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, 22908, VA, USA
- VIB/UGent Inflammation Research Centre, Biomedical Molecular Biology, Ghent University, 9052, Ghent, Belgium
| | - Martin Sauvageau
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada
- Molecular Biology Programs, Université de Montréal, Montréal, QC, H3T 1J4, Canada
- Department of Biochemistry, McGill University, Montréal, QC, H3G 1Y6, Canada
| | - Matthew J Smith
- Institute for Research in Immunology and Cancer, Université de Montréal, Montreal, QC, H3T 1J4, Canada
- Department of Pathology and Cell Biology, Université de Montréal, Montreal, QC, H3C 3J7, Canada
| | - Marie Kmita
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada
- Molecular Biology Programs, Université de Montréal, Montréal, QC, H3T 1J4, Canada
- Department of Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada
- Department of Experimental Medicine, McGill University, Montréal, QC, H3G 2M1, Canada
| | - Jean-François Côté
- Montreal Clinical Research Institute (IRCM), Montreal, QC, H2W 1R7, Canada.
- Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada.
- Molecular Biology Programs, Université de Montréal, Montréal, QC, H3T 1J4, Canada.
- Department of Medicine, Université de Montréal, Montreal, QC, H3C 3J7, Canada.
- Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 0C7, Canada.
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10
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Wu P, Yong P, Zhang Z, Xu R, Shang R, Shi J, Zhang J, Bi P, Chen E, Du S. Loss of Myomixer Results in Defective Myoblast Fusion, Impaired Muscle Growth, and Severe Myopathy in Zebrafish. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2022; 24:1023-1038. [PMID: 36083384 PMCID: PMC10112271 DOI: 10.1007/s10126-022-10159-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 08/25/2022] [Indexed: 06/15/2023]
Abstract
The development and growth of fish skeletal muscles require myoblast fusion to generate multinucleated myofibers. While zebrafish fast-twitch muscle can fuse to generate multinucleated fibers, the slow-twitch muscle fibers remain mononucleated in zebrafish embryos and larvae. The mechanism underlying the fiber-type-specific control of fusion remains elusive. Recent genetic studies using mice identified a long-sought fusion factor named Myomixer. To understand whether Myomixer is involved in the fiber-type specific fusion, we analyzed the transcriptional regulation of myomixer expression and characterized the muscle growth phenotype upon genetic deletion of myomixer in zebrafish. The data revealed that overexpression of Sonic Hedgehog (Shh) drastically inhibited myomixer expression and blocked myoblast fusion, recapitulating the phenotype upon direct genetic deletion of myomixer from zebrafish. The fusion defect in myomixer mutant embryos could be faithfully rescued upon re-expression of zebrafish myomixer gene or its orthologs from shark or human. Interestingly, myomixer mutant fish survived to adult stage though were notably smaller than wildtype siblings. Severe myopathy accompanied by the uncontrolled adipose infiltration was observed in both fast and slow muscle tissues of adult myomixer mutants. Collectively, our data highlight an indispensable role of myomixer gene for cell fusion during both embryonic muscle development and post-larval muscle growth.
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Affiliation(s)
- Ping Wu
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, USA
- Department of Bioengineering and Environmental Science, Changsha University, Changsha, China
| | - Pengzheng Yong
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, USA
| | - Zhanxiong Zhang
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, USA
| | - Rui Xu
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, USA
| | - Renjie Shang
- Center for Molecular Medicine & Department of Genetics, University of Georgia, Athens, USA
| | - Jun Shi
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, USA
- College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Jianshe Zhang
- Department of Bioengineering and Environmental Science, Changsha University, Changsha, China
| | - Pengpeng Bi
- Center for Molecular Medicine & Department of Genetics, University of Georgia, Athens, USA
| | - Elizabeth Chen
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, USA
| | - Shaojun Du
- Department of Biochemistry and Molecular Biology, Institute of Marine and Environmental Technology, University of Maryland School of Medicine, Baltimore, USA.
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11
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Phosphatidylserine orchestrates Myomerger membrane insertions to drive myoblast fusion. Proc Natl Acad Sci U S A 2022; 119:e2202490119. [PMID: 36095199 PMCID: PMC9499509 DOI: 10.1073/pnas.2202490119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Muscle cell fusion is a multistep process where the final step of the reaction drives progression beyond early hemifusion events to complete fusion. This step requires activity of the muscle-specific fusogen Myomerger, a single-pass transmembrane protein containing 84 amino acids with an ectodomain that includes two α-helices. Previous studies have demonstrated that Myomerger acts by destabilizing membranes through generation of elastic stresses in the outer leaflet of the plasma membrane. An obvious question is how such destabilizing activity might be regulated to avoid membrane and cellular damage, and how the two juxtaposed helices cooperate in fusion. Using cellular fusion assays and in vitro liposome assays, we report that the two helices possess unique characteristics, both of which are needed for full activity of the protein. We demonstrate that externalized phosphatidylserine (PS), a lipid previously implicated in myoblast fusion, has a determinant role in the regulation of Myomerger activity. The membrane-proximal, amphipathic Helix-1 is normally disordered and its α-helical structure is induced by PS, making membrane interactions more efficacious. The distal, more hydrophobic Helix-2 is intrinsically ordered, possesses an ability to insert into membranes, and augments the membrane-stressing effects of Helix-1. These data reveal that Myomerger fusogenic activity is an exquisitely orchestrated event involving its two ectodomain helices, which are controlled by membrane lipid composition, providing an explanation as to how its membrane-stressing activity is spatially and temporally regulated during the final step of myoblast fusion.
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