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Moses E, Atlan T, Sun X, Franěk R, Siddiqui A, Marinov GK, Shifman S, Zucker DM, Oron-Gottesman A, Greenleaf WJ, Cohen E, Ram O, Harel I. The killifish germline regulates longevity and somatic repair in a sex-specific manner. NATURE AGING 2024; 4:791-813. [PMID: 38750187 DOI: 10.1038/s43587-024-00632-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 04/10/2024] [Indexed: 05/22/2024]
Abstract
Classical evolutionary theories propose tradeoffs among reproduction, damage repair and lifespan. However, the specific role of the germline in shaping vertebrate aging remains largely unknown. In this study, we used the turquoise killifish (Nothobranchius furzeri) to genetically arrest germline development at discrete stages and examine how different modes of infertility impact life history. We first constructed a comprehensive single-cell gonadal atlas, providing cell-type-specific markers for downstream phenotypic analysis. We show here that germline depletion-but not arresting germline differentiation-enhances damage repair in female killifish. Conversely, germline-depleted males instead showed an extension in lifespan and rejuvenated metabolic functions. Through further transcriptomic analysis, we highlight enrichment of pro-longevity pathways and genes in germline-depleted male killifish and demonstrate functional conservation of how these factors may regulate longevity in germline-depleted Caenorhabditis elegans. Our results, therefore, demonstrate that different germline manipulation paradigms can yield pronounced sexually dimorphic phenotypes, implying alternative responses to classical evolutionary tradeoffs.
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Affiliation(s)
- Eitan Moses
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Tehila Atlan
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Xue Sun
- Department of Biochemistry, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Roman Franěk
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in Ceske Budejovice, Vodnany, Czech Republic
| | - Atif Siddiqui
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada (IMRIC), Hebrew University School of Medicine, Jerusalem, Israel
| | | | - Sagiv Shifman
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - David M Zucker
- Department of Statistics and Data Science, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Adi Oron-Gottesman
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, USA
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Ehud Cohen
- Department of Biochemistry and Molecular Biology, Institute for Medical Research Israel-Canada (IMRIC), Hebrew University School of Medicine, Jerusalem, Israel
| | - Oren Ram
- Department of Biochemistry, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Itamar Harel
- Department of Genetics, Silberman Institute, Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel.
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Moses E, Atlan T, Sun X, Franek R, Siddiqui A, Marinov GK, Shifman S, Zucker DM, Oron-Gottesman A, Greenleaf WJ, Cohen E, Ram O, Harel I. The killifish germline regulates longevity and somatic repair in a sex-specific manner. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.18.572041. [PMID: 38187630 PMCID: PMC10769255 DOI: 10.1101/2023.12.18.572041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Classical evolutionary theories propose tradeoffs between reproduction, damage repair, and lifespan. However, the specific role of the germline in shaping vertebrate aging remains largely unknown. Here, we use the turquoise killifish ( N. furzeri ) to genetically arrest germline development at discrete stages, and examine how different modes of infertility impact life-history. We first construct a comprehensive single-cell gonadal atlas, providing cell-type-specific markers for downstream phenotypic analysis. Next, we show that germline depletion - but not arresting germline differentiation - enhances damage repair in female killifish. Conversely, germline-depleted males instead showed an extension in lifespan and rejuvenated metabolic functions. Through further transcriptomic analysis, we highlight enrichment of pro-longevity pathways and genes in germline-depleted male killifish and demonstrate functional conservation of how these factors may regulate longevity in germline-depleted C. elegans . Our results therefore demonstrate that different germline manipulation paradigms can yield pronounced sexually dimorphic phenotypes, implying alternative responses to classical evolutionary tradeoffs.
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3
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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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Shakarchy A, Zarfati G, Hazak A, Mealem R, Huk K, Ziv T, Avinoam O, Zaritsky A. Machine learning inference of continuous single-cell state transitions during myoblast differentiation and fusion. Mol Syst Biol 2024; 20:217-241. [PMID: 38238594 PMCID: PMC10912675 DOI: 10.1038/s44320-024-00010-3] [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: 03/02/2023] [Revised: 12/19/2023] [Accepted: 01/04/2024] [Indexed: 03/06/2024] Open
Abstract
Cells modify their internal organization during continuous state transitions, supporting functions from cell division to differentiation. However, tools to measure dynamic physiological states of individual transitioning cells are lacking. We combined live-cell imaging and machine learning to monitor ERK1/2-inhibited primary murine skeletal muscle precursor cells, that transition rapidly and robustly from proliferating myoblasts to post-mitotic myocytes and then fuse, forming multinucleated myotubes. Our models, trained using motility or actin intensity features from single-cell tracking data, effectively tracked real-time continuous differentiation, revealing that differentiation occurs 7.5-14.5 h post induction, followed by fusion ~3 h later. Co-inhibition of ERK1/2 and p38 led to differentiation without fusion. Our model inferred co-inhibition leads to terminal differentiation, indicating that p38 is specifically required for transitioning from terminal differentiation to fusion. Our model also predicted that co-inhibition leads to changes in actin dynamics. Mass spectrometry supported these in silico predictions and suggested novel fusion and maturation regulators downstream of differentiation. Collectively, this approach can be adapted to various biological processes to uncover novel links between dynamic single-cell states and their functional outcomes.
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Affiliation(s)
- Amit Shakarchy
- Department of Software and Information Systems Engineering, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - Giulia Zarfati
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 761001, Israel
| | - Adi Hazak
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 761001, Israel
| | - Reut Mealem
- Department of Software and Information Systems Engineering, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - Karina Huk
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 761001, Israel
| | - Tamar Ziv
- The Smoler Proteomics Center, Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion Israel Institute of Technology, Haifa, 3200003, Israel
| | - Ori Avinoam
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, 761001, Israel.
| | - Assaf Zaritsky
- Department of Software and Information Systems Engineering, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel.
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Endo T. Postnatal skeletal muscle myogenesis governed by signal transduction networks: MAPKs and PI3K-Akt control multiple steps. Biochem Biophys Res Commun 2023; 682:223-243. [PMID: 37826946 DOI: 10.1016/j.bbrc.2023.09.048] [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: 07/19/2023] [Revised: 09/06/2023] [Accepted: 09/18/2023] [Indexed: 10/14/2023]
Abstract
Skeletal muscle myogenesis represents one of the most intensively and extensively examined systems of cell differentiation, tissue formation, and regeneration. Muscle regeneration provides an in vivo model system of postnatal myogenesis. It comprises multiple steps including muscle stem cell (or satellite cell) quiescence, activation, migration, myogenic determination, myoblast proliferation, myocyte differentiation, myofiber maturation, and hypertrophy. A variety of extracellular signaling and subsequent intracellular signal transduction pathways or networks govern the individual steps of postnatal myogenesis. Among them, MAPK pathways (the ERK, JNK, p38 MAPK, and ERK5 pathways) and PI3K-Akt signaling regulate multiple steps of myogenesis. Ca2+, cytokine, and Wnt signaling also participate in several myogenesis steps. These signaling pathways often control cell cycle regulatory proteins or the muscle-specific MyoD family and the MEF2 family of transcription factors. This article comprehensively reviews molecular mechanisms of the individual steps of postnatal skeletal muscle myogenesis by focusing on signal transduction pathways or networks. Nevertheless, no or only a partial signaling molecules or pathways have been identified in some responses during myogenesis. The elucidation of these unidentified signaling molecules and pathways leads to an extensive understanding of the molecular mechanisms of myogenesis.
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Affiliation(s)
- Takeshi Endo
- Department of Biology, Graduate School of Science, Chiba University, Yayoicho, Inageku, Chiba, Chiba 263-8522, Japan.
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Nguyen MT, Dash R, Jeong K, Lee W. Role of Actin-Binding Proteins in Skeletal Myogenesis. Cells 2023; 12:2523. [PMID: 37947600 PMCID: PMC10650911 DOI: 10.3390/cells12212523] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/22/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023] Open
Abstract
Maintenance of skeletal muscle quantity and quality is essential to ensure various vital functions of the body. Muscle homeostasis is regulated by multiple cytoskeletal proteins and myogenic transcriptional programs responding to endogenous and exogenous signals influencing cell structure and function. Since actin is an essential component in cytoskeleton dynamics, actin-binding proteins (ABPs) have been recognized as crucial players in skeletal muscle health and diseases. Hence, dysregulation of ABPs leads to muscle atrophy characterized by loss of mass, strength, quality, and capacity for regeneration. This comprehensive review summarizes the recent studies that have unveiled the role of ABPs in actin cytoskeletal dynamics, with a particular focus on skeletal myogenesis and diseases. This provides insight into the molecular mechanisms that regulate skeletal myogenesis via ABPs as well as research avenues to identify potential therapeutic targets. Moreover, this review explores the implications of non-coding RNAs (ncRNAs) targeting ABPs in skeletal myogenesis and disorders based on recent achievements in ncRNA research. The studies presented here will enhance our understanding of the functional significance of ABPs and mechanotransduction-derived myogenic regulatory mechanisms. Furthermore, revealing how ncRNAs regulate ABPs will allow diverse therapeutic approaches for skeletal muscle disorders to be developed.
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Affiliation(s)
- Mai Thi Nguyen
- Department of Biochemistry, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea; (M.T.N.); (K.J.)
| | - Raju Dash
- Department of Anatomy, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea;
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Republic of Korea
| | - Kyuho Jeong
- Department of Biochemistry, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea; (M.T.N.); (K.J.)
| | - Wan Lee
- Department of Biochemistry, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea; (M.T.N.); (K.J.)
- Channelopathy Research Center, Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Republic of Korea
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Moses E, Franek R, Harel I. A scalable and tunable platform for functional interrogation of peptide hormones in fish. eLife 2023; 12:e85960. [PMID: 37872843 PMCID: PMC10597582 DOI: 10.7554/elife.85960] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 09/16/2023] [Indexed: 10/25/2023] Open
Abstract
Pituitary hormones play a central role in shaping vertebrate life history events, including growth, reproduction, metabolism, and aging. The regulation of these traits often requires precise control of hormone levels across diverse timescales. However, fine tuning circulating hormones in-vivo has traditionally been experimentally challenging. Here, using the naturally short-lived turquoise killifish (N. furzeri), we describe a high-throughput platform that combines loss- and gain-of-function of peptide hormones. Mutation of three primary pituitary hormones, growth hormone (gh1), follicle stimulating hormone (fshb), and thyroid stimulating hormone (tshb), alters somatic growth and reproduction. Thus, suggesting that while the killifish undergoes extremely rapid growth and maturity, it still relies on vertebrate-conserved genetic networks. As the next stage, we developed a gain-of-function vector system in which a hormone is tagged using a self-cleavable fluorescent reporter, and ectopically expressed in-vivo through intramuscular electroporation. Following a single electroporation, phenotypes, such as reproduction, are stably rescued for several months. Notably, we demonstrate the versatility of this approach by using multiplexing, dose-dependent, and doxycycline-inducible systems to achieve tunable and reversible expression. In summary, this method is relatively high-throughput, and facilitates large-scale interrogation of life-history strategies in fish. Ultimately, this approach could be adapted for modifying aquaculture species and exploring pro-longevity interventions.
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Affiliation(s)
- Eitan Moses
- Department of Genetics, the Silberman Institute, The Hebrew University of JerusalemJerusalemIsrael
| | - Roman Franek
- Department of Genetics, the Silberman Institute, The Hebrew University of JerusalemJerusalemIsrael
- University of South Bohemia in Ceske Budejovice, South Bohemian Research Center of Aquaculture and Biodiversity of HydrocenosesVodnanyCzech Republic
| | - Itamar Harel
- Department of Genetics, the Silberman Institute, The Hebrew University of JerusalemJerusalemIsrael
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Kalailingam P, Verma A, Lee YH, Thanabalu T. Conditional Knockout of N-WASP Enhanced the Formation of Keratinizing Squamous Cell Carcinoma Induced by KRas G12D. Cancers (Basel) 2023; 15:4455. [PMID: 37760426 PMCID: PMC10526518 DOI: 10.3390/cancers15184455] [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: 07/14/2023] [Revised: 08/15/2023] [Accepted: 08/21/2023] [Indexed: 09/29/2023] Open
Abstract
Squamous cell carcinoma (SCC) is one of the most common forms of skin cancer in humans, and Neural Wiskott-Aldrich Syndrome Protein (N-WASP) plays a crucial role in epidermal homeostasis. To elucidate the role of N-WASP in skin cancer, we generated mice which expressed constitutively active KRas (KRasG12D) in keratinocytes with either homozygous (N-WASPKOG12D) or heterozygous (N-WASPHetG12D) N-WASP knockout upon Tamoxifen (TAM) injection. Both the N-WASPKOG12D and N-WASPHetG12D mice had similar body weights and no congenital malformations prior to the injection of TAM. Within 2 weeks of the injections, the N-WASPKOG12D mice exhibited significant reductions in weight coupled with visible tumors at numerous sites, unlike the N-WASPHetG12D mice, which had no visible tumors. We found that both sets of mice had oily, sticky skin and wet eyes 3 weeks after their exposure to TAM, indicating the overproduction of sebum/meibum. At 37 days post TAM injection, several notable observations were made. Tumors collected from the N-WASPKOG12D mice had small- to large-sized keratin pearls that were not observed in the N-WASPHetG12D mice. A Western blot and immunostaining analysis both highlighted significantly higher levels of expression of SCC markers, such as the cytokeratins 8, 17, 18, and 19 and TP63, in the tumors of the N-WASPKOG12D mice compared to those of the latter group. Furthermore, we noted increases in the expression levels of EGFR, P-ERK, GLUT1, P-mTOR, and P-4EBP in the N-WASPKOG12D mice, suggesting that the deletion of N-WASP in the keratinocytes enhanced KRas signaling and glucose uptake, resulting in aggressive tumor formation. Interestingly, a thickening of the epidermal layer within the esophagus and tongue was only observed in the N-WASPKOG12D mice. Immunostaining for PCNA emphasized a significantly higher number of PCNA-positive cells in the skin of the N-WASPKOG12D mice compared to their counterparts, implying that epidermal thickening and enhanced tumorigenesis are due to an increased proliferation of keratinocytes. Through our results, we have established that N-WASP plays a tumor-suppressive role in skin cancer.
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Affiliation(s)
| | | | | | - Thirumaran Thanabalu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore; (P.K.); (A.V.); (Y.H.L.)
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Astre G, Atlan T, Goshtchevsky U, Oron-Gottesman A, Smirnov M, Shapira K, Velan A, Deelen J, Levy T, Levanon EY, Harel I. Genetic perturbation of AMP biosynthesis extends lifespan and restores metabolic health in a naturally short-lived vertebrate. Dev Cell 2023; 58:1350-1364.e10. [PMID: 37321215 DOI: 10.1016/j.devcel.2023.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 03/09/2023] [Accepted: 05/23/2023] [Indexed: 06/17/2023]
Abstract
During aging, the loss of metabolic homeostasis drives a myriad of pathologies. A central regulator of cellular energy, the AMP-activated protein kinase (AMPK), orchestrates organismal metabolism. However, direct genetic manipulations of the AMPK complex in mice have, so far, produced detrimental phenotypes. Here, as an alternative approach, we alter energy homeostasis by manipulating the upstream nucleotide pool. Using the turquoise killifish, we mutate APRT, a key enzyme in AMP biosynthesis, and extend the lifespan of heterozygous males. Next, we apply an integrated omics approach to show that metabolic functions are rejuvenated in old mutants, which also display a fasting-like metabolic profile and resistance to high-fat diet. At the cellular level, heterozygous cells exhibit enhanced nutrient sensitivity, reduced ATP levels, and AMPK activation. Finally, lifelong intermittent fasting abolishes the longevity benefits. Our findings suggest that perturbing AMP biosynthesis may modulate vertebrate lifespan and propose APRT as a promising target for promoting metabolic health.
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Affiliation(s)
- Gwendoline Astre
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Tehila Atlan
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Uri Goshtchevsky
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Adi Oron-Gottesman
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Margarita Smirnov
- Central Fish Health Laboratory, Department of Fisheries and Aquaculture, Ministry of Agriculture and Rural Development, Nir David 10803, Israel
| | - Kobi Shapira
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Ariel Velan
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Joris Deelen
- Max Planck Institute for Biology of Ageing, Cologne 50931, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Ageing-Associated Diseases (CECAD), University of Cologne, Cologne 50931, Germany
| | - Tomer Levy
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Erez Y Levanon
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Itamar Harel
- Department of Genetics, the Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel.
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Dittmar T, Hass R. Intrinsic signalling factors associated with cancer cell-cell fusion. Cell Commun Signal 2023; 21:68. [PMID: 37016404 PMCID: PMC10071245 DOI: 10.1186/s12964-023-01085-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/21/2023] [Indexed: 04/06/2023] Open
Abstract
Cellular fusion e.g. between cancer cells and normal cells represents a stepwise process that is tightly regulated. During a pre-hybrid preparation program somatic cells and/or cancer cells are promoted to a pro-fusogenic state as a prerequisite to prepare a fusion process. A pro-fusogenic state requires significant changes including restructure of the cytoskeleton, e.g., by the formation of F-actin. Moreover, distinct plasma membrane lipids such as phosphatidylserine play an important role during cell fusion. In addition, the expression of distinct fusogenic factors such as syncytins and corresponding receptors are of fundamental importance to enable cellular mergers. Subsequent hybrid formation and fusion are followed by a post-hybrid selection process. Fusion among normal cells is important and often required during organismal development. Cancer cells fusion appears more rarely and is associated with the generation of new cancer hybrid cell populations. These cancer hybrid cells contribute to an elevated tumour plasticity by altered metastatic behaviour, changes in therapeutic and apoptotic responses, and even in the formation of cancer stem/ initiating cells. While many parts within this multi-step cascade are still poorly understood, this review article predominantly focusses on the intracellular necessities for fusion among cancer cells or with other cell populations of the tumour microenvironment. Video Abstract.
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Affiliation(s)
- Thomas Dittmar
- Institute of Immunology, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Stockumer Str. 10, 58448, Witten, Germany.
| | - Ralf Hass
- Biochemistry and Tumor Biology Laboratory, Department of Obstetrics and Gynaecology, Hannover Medical School, 30625, Hannover, Germany.
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11
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Campellone KG, Lebek NM, King VL. Branching out in different directions: Emerging cellular functions for the Arp2/3 complex and WASP-family actin nucleation factors. Eur J Cell Biol 2023; 102:151301. [PMID: 36907023 DOI: 10.1016/j.ejcb.2023.151301] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 02/07/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
The actin cytoskeleton impacts practically every function of a eukaryotic cell. Historically, the best-characterized cytoskeletal activities are in cell morphogenesis, motility, and division. The structural and dynamic properties of the actin cytoskeleton are also crucial for establishing, maintaining, and changing the organization of membrane-bound organelles and other intracellular structures. Such activities are important in nearly all animal cells and tissues, although distinct anatomical regions and physiological systems rely on different regulatory factors. Recent work indicates that the Arp2/3 complex, a broadly expressed actin nucleator, drives actin assembly during several intracellular stress response pathways. These newly described Arp2/3-mediated cytoskeletal rearrangements are coordinated by members of the Wiskott-Aldrich Syndrome Protein (WASP) family of actin nucleation-promoting factors. Thus, the Arp2/3 complex and WASP-family proteins are emerging as crucial players in cytoplasmic and nuclear activities including autophagy, apoptosis, chromatin dynamics, and DNA repair. Characterizations of the functions of the actin assembly machinery in such stress response mechanisms are advancing our understanding of both normal and pathogenic processes, and hold great promise for providing insights into organismal development and interventions for disease.
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Affiliation(s)
- Kenneth G Campellone
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA.
| | - Nadine M Lebek
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA
| | - Virginia L King
- Department of Molecular and Cell Biology, Institute for Systems Genomics; University of Connecticut; Storrs, CT, USA
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12
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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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13
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Monocyte-Macrophage Lineage Cell Fusion. Int J Mol Sci 2022; 23:ijms23126553. [PMID: 35742997 PMCID: PMC9223484 DOI: 10.3390/ijms23126553] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/07/2022] [Accepted: 06/10/2022] [Indexed: 02/06/2023] Open
Abstract
Cell fusion (fusogenesis) occurs in natural and pathological conditions in prokaryotes and eukaryotes. Cells of monocyte–macrophage lineage are highly fusogenic. They create syncytial multinucleated giant cells (MGCs) such as osteoclasts (OCs), MGCs associated with the areas of infection/inflammation, and foreign body-induced giant cells (FBGCs). The fusion of monocytes/macrophages with tumor cells may promote cancer metastasis. We describe types and examples of monocyte–macrophage lineage cell fusion and the role of actin-based structures in cell fusion.
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14
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Regulation of the myoblast fusion reaction for muscle development, regeneration, and adaptations. Exp Cell Res 2022; 415:113134. [PMID: 35367215 DOI: 10.1016/j.yexcr.2022.113134] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 02/23/2022] [Accepted: 03/28/2022] [Indexed: 12/27/2022]
Abstract
Fusion of plasma membranes is essential for skeletal muscle development, regeneration, exercise-induced adaptations, and results in a cell that contains hundreds to thousands of nuclei within a shared cytoplasm. The differentiation process in myocytes culminates in their fusion to form a new myofiber or fusion to an existing myofiber thereby contributing more synthetic material to the syncytium. The choice for two cells to fuse and become one could be a dangerous event if the two cells are not committed to an allied function. Thus, fusion events are highly regulated with positive and negative factors to fine-tune the process, and requires muscle-specific fusogens (Myomaker and Myomerger) as well as general cellular machinery to achieve the union of membranes. While a unified vertebrate myoblast fusion pathway is not yet established, recent discoveries should make this pursuit attainable. Not only does myocyte fusion impact the normal biology of skeletal muscle, but new evidence indicates dysregulation of the process impacts pathologies of skeletal muscle. Here, I will highlight the molecular players and biochemical mechanisms that drive fusion events in muscle, and discuss how this key myogenic process impacts skeletal muscle diseases.
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15
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Aase-Remedios ME, Coll-Lladó C, Ferrier DEK. Amphioxus muscle transcriptomes reveal vertebrate-like myoblast fusion genes and a highly conserved role of insulin signalling in the metabolism of muscle. BMC Genomics 2022; 23:93. [PMID: 35105312 PMCID: PMC8805411 DOI: 10.1186/s12864-021-08222-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The formation and functioning of muscles are fundamental aspects of animal biology, and the evolution of 'muscle genes' is central to our understanding of this tissue. Feeding-fasting-refeeding experiments have been widely used to assess muscle cellular and metabolic responses to nutrition. Though these studies have focused on vertebrate models and only a few invertebrate systems, they have found similar processes are involved in muscle degradation and maintenance. Motivation for these studies stems from interest in diseases whose pathologies involve muscle atrophy, a symptom also triggered by fasting, as well as commercial interest in the muscle mass of animals kept for consumption. Experimentally modelling atrophy by manipulating nutritional state causes muscle mass to be depleted during starvation and replenished with refeeding so that the genetic mechanisms controlling muscle growth and degradation can be understood. RESULTS Using amphioxus, the earliest branching chordate lineage, we address the gap in previous work stemming from comparisons between distantly related vertebrate and invertebrate models. Our amphioxus feeding-fasting-refeeding muscle transcriptomes reveal a highly conserved myogenic program and that the pro-orthologues of many vertebrate myoblast fusion genes were present in the ancestral chordate, despite these invertebrate chordates having unfused mononucleate myocytes. We found that genes differentially expressed between fed and fasted amphioxus were orthologous to the genes that respond to nutritional state in vertebrates. This response is driven in a large part by the highly conserved IGF/Akt/FOXO pathway, where depleted nutrient levels result in activation of FOXO, a transcription factor with many autophagy-related gene targets. CONCLUSION Reconstruction of these gene networks and pathways in amphioxus muscle provides a key point of comparison between the distantly related groups assessed thus far, significantly refining the reconstruction of the ancestral state for chordate myoblast fusion genes and identifying the extensive role of duplicated genes in the IGF/Akt/FOXO pathway across animals. Our study elucidates the evolutionary trajectory of muscle genes as they relate to the increased complexity of vertebrate muscles and muscle development.
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Affiliation(s)
- Madeleine E Aase-Remedios
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
| | - Clara Coll-Lladó
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK
| | - David E K Ferrier
- The Scottish Oceans Institute, Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK.
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16
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YAP1 nuclear efflux and transcriptional reprograming follow membrane diminution upon VSV-G-induced cell fusion. Nat Commun 2021; 12:4502. [PMID: 34301937 PMCID: PMC8302681 DOI: 10.1038/s41467-021-24708-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/24/2021] [Indexed: 02/07/2023] Open
Abstract
Cells in many tissues, such as bone, muscle, and placenta, fuse into syncytia to acquire new functions and transcriptional programs. While it is known that fused cells are specialized, it is unclear whether cell-fusion itself contributes to programmatic-changes that generate the new cellular state. Here, we address this by employing a fusogen-mediated, cell-fusion system to create syncytia from undifferentiated cells. RNA-Seq analysis reveals VSV-G-induced cell fusion precedes transcriptional changes. To gain mechanistic insights, we measure the plasma membrane surface area after cell-fusion and observe it diminishes through increases in endocytosis. Consequently, glucose transporters internalize, and cytoplasmic glucose and ATP transiently decrease. This reduced energetic state activates AMPK, which inhibits YAP1, causing transcriptional-reprogramming and cell-cycle arrest. Impairing either endocytosis or AMPK activity prevents YAP1 inhibition and cell-cycle arrest after fusion. Together, these data demonstrate plasma membrane diminishment upon cell-fusion causes transient nutrient stress that may promote transcriptional-reprogramming independent from extrinsic cues.
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17
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Abstract
During multicellular organism development, complex structures are sculpted to form organs and tissues, which are maintained throughout adulthood. Many of these processes require cells to fuse with one another, or with themselves. These plasma membrane fusions merge endoplasmic cellular content across external, exoplasmic, space. In the nematode Caenorhabditis elegans, such cell fusions serve as a unique sculpting force, involved in the embryonic morphogenesis of the skin-like multinuclear hypodermal cells, but also in refining delicate structures, such as valve openings and the tip of the tail. During post-embryonic development, plasma membrane fusions continue to shape complex neuron structures and organs such as the vulva, while during adulthood fusion participates in cell and tissue repair. These processes rely on two fusion proteins (fusogens): EFF-1 and AFF-1, which are part of a broader family of structurally related membrane fusion proteins, encompassing sexual reproduction, viral infection, and tissue remodeling. The established capabilities of these exoplasmic fusogens are further expanded by new findings involving EFF-1 and AFF-1 in endocytic vesicle fission and phagosome sealing. Tight regulation by cell-autonomous and non-cell autonomous mechanisms orchestrates these diverse cell fusions at the correct place and time-these processes and their significance are discussed in this review.
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18
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Cracknell T, Mannsverk S, Nichols A, Dowle A, Blanco G. Proteomic resolution of IGFN1 complexes reveals a functional interaction with the actin nucleating protein COBL. Exp Cell Res 2020; 395:112179. [PMID: 32768501 PMCID: PMC7584501 DOI: 10.1016/j.yexcr.2020.112179] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/06/2020] [Accepted: 07/11/2020] [Indexed: 01/09/2023]
Abstract
The Igfn1 gene produces multiple proteins by alternative splicing predominantly expressed in skeletal muscle. Igfn1 deficient clones derived from C2C12 myoblasts show reduced fusion index and morphological differences compared to control myotubes. Here, we first show that G:F actin ratios are significantly higher in differentiating IGFN1-deficient C2C12 myoblasts, suggesting that fusion and differentiation defects are underpinned by deficient actin remodelling. We obtained pull-downs from skeletal muscle with IGFN1 fragments and applied a proteomics approach. The proteomic composition of IGFN1 complexes identified the cytoskeleton and an association with the proteasome as the main networks. The actin nucleating protein COBL was selected for further validation. COBL is expressed in C2C12 myoblasts from the first stages of myoblast fusion but not in proliferating cells. COBL is also expressed in adult muscle and, as IGFN1, localizes to the Z-disc. We show that IGFN1 interacts, stabilizes and colocalizes with COBL and prevents the ability of COBL to form actin ruffles in COS7 cells. COBL loss of function C2C12-derived clones are able to fuse, therefore indicating that COBL or the IGFN1/COBL interaction are not essential for myoblast fusion.
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Affiliation(s)
| | - Steinar Mannsverk
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Angus Nichols
- Department of Biology, University of York, York, YO32 5UQ, UK
| | - Adam Dowle
- Technology Facility, Department of Biology, University of York, York, YO32 5UQ, UK
| | - Gonzalo Blanco
- Department of Biology, University of York, York, YO32 5UQ, UK.
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19
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Murach KA, Vechetti IJ, Van Pelt DW, Crow SE, Dungan CM, Figueiredo VC, Kosmac K, Fu X, Richards CI, Fry CS, McCarthy JJ, Peterson CA. Fusion-Independent Satellite Cell Communication to Muscle Fibers During Load-Induced Hypertrophy. FUNCTION 2020; 1:zqaa009. [PMID: 32864621 PMCID: PMC7448100 DOI: 10.1093/function/zqaa009] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 01/06/2023] Open
Abstract
The "canonical" function of Pax7+ muscle stem cells (satellite cells) during hypertrophic growth of adult muscle fibers is myonuclear donation via fusion to support increased transcriptional output. In recent years, however, emerging evidence suggests that satellite cells play an important secretory role in promoting load-mediated growth. Utilizing genetically modified mouse models of delayed satellite cell fusion and in vivo extracellular vesicle (EV) tracking, we provide evidence for satellite cell communication to muscle fibers during hypertrophy. Myogenic progenitor cell-EV-mediated communication to myotubes in vitro influences extracellular matrix (ECM)-related gene expression, which is congruent with in vivo overload experiments involving satellite cell depletion, as well as in silico analyses. Satellite cell-derived EVs can transfer a Cre-induced, cytoplasmic-localized fluorescent reporter to muscle cells as well as microRNAs that regulate ECM genes such as matrix metalloproteinase 9 (Mmp9), which may facilitate growth. Delayed satellite cell fusion did not limit long-term load-induced muscle hypertrophy indicating that early fusion-independent communication from satellite cells to muscle fibers is an underappreciated aspect of satellite cell biology. We cannot exclude the possibility that satellite cell-mediated myonuclear accretion is necessary to maintain prolonged growth, specifically in the later phases of adaptation, but these data collectively highlight how EV delivery from satellite cells can directly contribute to mechanical load-induced muscle fiber hypertrophy, independent of cell fusion to the fiber.
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Affiliation(s)
- Kevin A Murach
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Ivan J Vechetti
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Douglas W Van Pelt
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Samuel E Crow
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Cory M Dungan
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Vandre C Figueiredo
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Kate Kosmac
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Xu Fu
- Department of Chemistry, College of Arts and Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Christopher I Richards
- Department of Chemistry, College of Arts and Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - Christopher S Fry
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Athletic Training and Clinical Nutrition, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
| | - John J McCarthy
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
| | - Charlotte A Peterson
- The Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, Lexington, KY 40536, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA
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20
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Barzilai-Tutsch H, Genin O, Pines M, Halevy O. Early pathological signs in young dysf -/- mice are improved by halofuginone. Neuromuscul Disord 2020; 30:472-482. [PMID: 32451154 DOI: 10.1016/j.nmd.2020.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 03/14/2020] [Accepted: 04/03/2020] [Indexed: 01/09/2023]
Abstract
Dysferlinopathies are a non-lethal group of late-onset muscular dystrophies. Here, we evaluated the fusion ability of primary myoblasts from young dysf-/- mice and the muscle histopathology prior to, and during early stages of disease onset. The ability of primary myoblasts of 5-week-old dysf-/- mice to form large myotubes was delayed compared to their wild-type counterparts, as evaluated by scanning electron microscopy. However, their fusion activity, as reflected by the presence of actin filaments connecting several cells, was enhanced by the antifibrotic drug halofuginone. Early dystrophic signs were already apparent in 4-week-old dysf-/- mice; their collagen level was double that in wild-type mice and continued to rise until 5 months of age. Continuous treatment with halofuginone from 4 weeks to 5 months of age reduced muscle fibrosis in a phosphorylated-Smad3 inhibition-related manner. Halofuginone also enhanced myofiber hypertrophy, reduced the percentage of centrally nucleated myofibers, and increased muscle performance. Together, the data suggest an inhibitory effect of halofuginone on the muscle histopathology at very early stages of dysferlinopathy, and enhancement of muscle performance. These results offer new opportunities for early pharmaceutical treatment in dysferlinopathies with favorable outcomes at later stages of life.
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Affiliation(s)
- Hila Barzilai-Tutsch
- Department of Animal Sciences, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel
| | - Olga Genin
- Institute of Animal Science, the Volcani Center, Bet Dagan 52505, Israel
| | - Mark Pines
- Institute of Animal Science, the Volcani Center, Bet Dagan 52505, Israel
| | - Orna Halevy
- Department of Animal Sciences, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel.
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21
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Chen B, You W, Wang Y, Shan T. The regulatory role of Myomaker and Myomixer-Myomerger-Minion in muscle development and regeneration. Cell Mol Life Sci 2020; 77:1551-1569. [PMID: 31642939 PMCID: PMC11105057 DOI: 10.1007/s00018-019-03341-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022]
Abstract
Skeletal muscle plays essential roles in motor function, energy, and glucose metabolism. Skeletal muscle formation occurs through a process called myogenesis, in which a crucial step is the fusion of mononucleated myoblasts to form multinucleated myofibers. The myoblast/myocyte fusion is triggered and coordinated in a muscle-specific way that is essential for muscle development and post-natal muscle regeneration. Many molecules and proteins have been found and demonstrated to have the capacity to regulate the fusion of myoblast/myocytes. Interestingly, two newly discovered muscle-specific membrane proteins, Myomaker and Myomixer (also called Myomerger and Minion), have been identified as fusogenic regulators in vertebrates. Both Myomaker and Myomixer-Myomerger-Minion have the capacity to directly control the myogenic fusion process. Here, we review and discuss the latest studies related to these two proteins, including the discovery, structure, expression pattern, functions, and regulation of Myomaker and Myomixer-Myomerger-Minion. We also emphasize and discuss the interaction between Myomaker and Myomixer-Myomerger-Minion, as well as their cooperative regulatory roles in cell-cell fusion. Moreover, we highlight the areas for exploration of Myomaker and Myomixer-Myomerger-Minion in future studies and consider their potential application to control cell fusion for cell-therapy purposes.
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Affiliation(s)
- Bide Chen
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, China
- The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou, China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Hangzhou, China
| | - Wenjing You
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, China
- The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou, China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Hangzhou, China
| | - Yizhen Wang
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, China
- The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou, China
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Hangzhou, China
| | - Tizhong Shan
- College of Animal Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, China.
- The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou, China.
- Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Hangzhou, China.
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22
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Petrany MJ, Millay DP. Cell Fusion: Merging Membranes and Making Muscle. Trends Cell Biol 2019; 29:964-973. [PMID: 31648852 PMCID: PMC7849503 DOI: 10.1016/j.tcb.2019.09.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 12/12/2022]
Abstract
Cell fusion is essential for the development of multicellular organisms, and plays a key role in the formation of various cell types and tissues. Recent findings have highlighted the varied protein machinery that drives plasma-membrane merger in different systems, which is characterized by diverse structural and functional elements. We highlight the discovery and activities of several key sets of fusion proteins that together offer an evolving perspective on cell membrane fusion. We also emphasize recent discoveries in vertebrate myoblast fusion in skeletal muscle, which is composed of numerous multinucleated myofibers formed by the fusion of progenitor cells during development.
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Affiliation(s)
- Michael J Petrany
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Douglas P Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
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23
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NADPH Oxidase 4 Contributes to Myoblast Fusion and Skeletal Muscle Regeneration. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:3585390. [PMID: 31827673 PMCID: PMC6885834 DOI: 10.1155/2019/3585390] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/24/2019] [Accepted: 10/08/2019] [Indexed: 01/28/2023]
Abstract
Myoblast fusion is an essential step in skeletal muscle development and regeneration. NADPH oxidase 4 (Nox4) regulates cellular processes such as proliferation, differentiation, and survival by producing reactive oxygen species (ROS). Insulin-like growth factor 1 induces muscle hypertrophy via Nox4, but its function in myoblast fusion remains elusive. Here, we report a ROS-dependent role of Nox4 in myoblast differentiation. Regenerating muscle fibers after injury by cardiotoxin had a lower cross-sectional area in Nox4-knockout (KO) mice than myofibers in wild-type (WT) mice. Diameters and fusion index values of myotubes differentiated from Nox4-KO primary myoblasts were significantly lower than those of myotubes derived from WT myoblasts. However, no difference was observed in the differentiation index and expression of MyoD, myogenin, and myosin heavy chain 3 (MHC) between KO and WT myotubes. The decreased fusion index was also observed during differentiation of primary myoblasts and C2C12 cells with suppressed Nox4 expression. In contrast, in C2C12 cells overexpressing Nox4, the fusion index was increased, whereas the differentiation index and MHC and myogenin protein expression were not affected compared to control. Interestingly, the expression of myomaker (Tmem8c), a fusogenic protein that controls myoblast fusion, was reduced in Nox4-knockdown C2C12 cells. The myomaker expression level was proportional to the cellular ROS level, which was regulated by of Nox4 expression level. These results suggests that Nox4 contributes to myoblast fusion, possibly through the regulation of myomaker expression via ROS production, and that Nox4-dependent ROS may promote skeletal muscle regeneration and growth.
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24
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Abstract
Cell-cell fusion is a fundamental process underlying fertilization, development, regeneration and physiology of metazoans. It is a multi-step process involving cell recognition and adhesion, actin cytoskeletal rearrangements, fusogen engagement, lipid mixing and fusion pore formation, ultimately resulting in the integration of two fusion partners. Here, we focus on the asymmetric actin cytoskeletal rearrangements at the site of fusion, known as the fusogenic synapse, which was first discovered during myoblast fusion in Drosophila embryos and later also found in mammalian muscle and non-muscle cells. At the asymmetric fusogenic synapse, actin-propelled invasive membrane protrusions from an attacking fusion partner trigger actomyosin-based mechanosensory responses in the receiving cell. The interplay between the invasive and resisting forces generated by the two fusion partners puts the fusogenic synapse under high mechanical tension and brings the two cell membranes into close proximity, promoting the engagement of fusogens to initiate fusion pore formation. In this Cell Science at a Glance article and the accompanying poster, we highlight the molecular, cellular and biophysical events at the asymmetric fusogenic synapse using Drosophila myoblast fusion as a model.
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Affiliation(s)
- Ji Hoon Kim
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Elizabeth H Chen
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA .,Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
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25
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Faust JJ, Balabiyev A, Heddleston JM, Podolnikova NP, Baluch DP, Chew TL, Ugarova TP. An actin-based protrusion originating from a podosome-enriched region initiates macrophage fusion. Mol Biol Cell 2019; 30:2254-2267. [PMID: 31242090 PMCID: PMC6743464 DOI: 10.1091/mbc.e19-01-0009] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Macrophage fusion resulting in the formation of multinucleated giant cells occurs in a variety of chronic inflammatory diseases, yet the mechanism responsible for initiating this process is unknown. Here, we used live cell imaging to show that actin-based protrusions at the leading edge initiate macrophage fusion. Phase-contrast video microscopy demonstrated that in the majority of events, short protrusions (∼3 µm) between two closely apposed cells initiated fusion, but occasionally we observed long protrusions (∼12 µm). Using macrophages isolated from LifeAct mice and imaging with lattice light sheet microscopy, we further found that fusion-competent protrusions formed at sites enriched in podosomes. Inducing fusion in mixed populations of GFP- and mRFP-LifeAct macrophages showed rapid spatial overlap between GFP and RFP signal at the site of fusion. Cytochalasin B strongly reduced fusion and when rare fusion events occurred, protrusions were not observed. Fusion of macrophages deficient in Wiskott-Aldrich syndrome protein and Cdc42, key molecules involved in the formation of actin-based protrusions and podosomes, was also impaired both in vitro and in vivo. Finally, inhibiting the activity of the Arp2/3 complex decreased fusion and podosome formation. Together these data suggest that an actin-based protrusion formed at the leading edge initiates macrophage fusion.
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Affiliation(s)
- James J Faust
- School of Life Sciences, Arizona State University, Tempe, AZ 85287
| | - Arnat Balabiyev
- School of Life Sciences, Arizona State University, Tempe, AZ 85287
| | - John M Heddleston
- Advanced Imaging Center, HHMI Janelia Research Campus, Ashburn, VA 20147
| | | | - D Page Baluch
- School of Life Sciences, Arizona State University, Tempe, AZ 85287
| | - Teng-Leong Chew
- Advanced Imaging Center, HHMI Janelia Research Campus, Ashburn, VA 20147
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26
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Naa15 knockdown enhances c2c12 myoblast fusion and induces defects in zebrafish myotome morphogenesis. Comp Biochem Physiol B Biochem Mol Biol 2018; 228:61-67. [PMID: 30502388 DOI: 10.1016/j.cbpb.2018.11.005] [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: 09/19/2018] [Revised: 11/16/2018] [Accepted: 11/21/2018] [Indexed: 11/21/2022]
Abstract
The understanding of muscle tissue formation and regeneration is essential for the development of therapeutic approaches to treat muscle diseases or loss of muscle mass and strength during ageing or cancer. One of the critical steps in muscle formation is the fusion of muscle cells to form or regenerate muscle fibres. To identify new genes controlling myoblast fusion, we performed a siRNA screen in c2c12 myoblasts. The genes identified during this screen were then studied in vivo by knockdown in zebrafish using morpholino. We found that N-alpha-acetyltransferase 15 (Naa15) knockdown enhanced c2c12 myoblast fusion, suggesting that Naa15 negatively regulates myogenic cell fusion. We identified two Naa15 orthologous genes in the zebrafish genome: Naa15a and Naa15b. These two orthologs were expressed in the myogenic domain of the somite. Knockdown of zebrafish Naa15a and Naa15b genes induced a "U"-shaped segmentation of the myotome and alteration of myotome boundaries, resulting in the formation of abnormally long myofibres spanning adjacent somites. Taken together, these results show that Naa15 regulates myotome formation and myogenesis in fish.
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27
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Hamoud N, Tran V, Aimi T, Kakegawa W, Lahaie S, Thibault MP, Pelletier A, Wong GW, Kim IS, Kania A, Yuzaki M, Bouvier M, Côté JF. Spatiotemporal regulation of the GPCR activity of BAI3 by C1qL4 and Stabilin-2 controls myoblast fusion. Nat Commun 2018; 9:4470. [PMID: 30367035 PMCID: PMC6203814 DOI: 10.1038/s41467-018-06897-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 10/05/2018] [Indexed: 11/09/2022] Open
Abstract
Myoblast fusion is tightly regulated during development and regeneration of muscle fibers. BAI3 is a receptor that orchestrates myoblast fusion via Elmo/Dock1 signaling, but the mechanisms regulating its activity remain elusive. Here we report that mice lacking BAI3 display small muscle fibers and inefficient muscle regeneration after cardiotoxin-induced injury. We describe two proteins that repress or activate BAI3 in muscle progenitors. We find that the secreted C1q-like1-4 proteins repress fusion by specifically interacting with BAI3. Using a proteomic approach, we identify Stabilin-2 as a protein that interacts with BAI3 and stimulates its fusion promoting activity. We demonstrate that Stabilin-2 activates the GPCR activity of BAI3. The resulting activated heterotrimeric G-proteins contribute to the initial recruitment of Elmo proteins to the membrane, which are then stabilized on BAI3 through a direct interaction. Collectively, our results demonstrate that the activity of BAI3 is spatiotemporally regulated by C1qL4 and Stabilin-2 during myoblast fusion.
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Affiliation(s)
- Noumeira Hamoud
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Département de Médecine (Programmes de Biologie Moléculaire), Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Viviane Tran
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Takahiro Aimi
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Wataru Kakegawa
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Sylvie Lahaie
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Integrated Program in Neuroscience, McGill University, Montréal, QC, H3A 2B4, Canada
| | - Marie-Pier Thibault
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada
| | - Ariane Pelletier
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada
| | - G William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Center for Metabolism and Obesity Research, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - In-San Kim
- Biomedical Research Institute, Korea Institute Science and Technology, Seoul, 136-791, Republic of Korea.,KU-KIST school, Korea University, Seoul, 136-701, Republic of Korea
| | - Artur Kania
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada.,Integrated Program in Neuroscience, McGill University, Montréal, QC, H3A 2B4, Canada.,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 1A3, Canada
| | - Michisuke Yuzaki
- Department of Physiology, Keio University School of Medicine, Tokyo, 160-8582, Japan.,Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JT), Tokyo, 102-0075, Japan
| | - Michel Bouvier
- Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada.,Institut de Recherches en Immunologie et Cancérologie (IRIC), Université de Montréal, Montréal, QC, Canada, H3C 3J7
| | - Jean-François Côté
- Institut de Recherches Cliniques de Montréal (IRCM), Montréal, QC, H2W 1R7, Canada. .,Département de Médecine (Programmes de Biologie Moléculaire), Université de Montréal, Montréal, QC, H3T 1J4, Canada. .,Département de Biochimie, Université de Montréal, Montréal, QC, H3T 1J4, Canada. .,Department of Anatomy and Cell Biology, McGill University, Montréal, QC, H3A 1A3, Canada.
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28
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Leikina E, Gamage DG, Prasad V, Goykhberg J, Crowe M, Diao J, Kozlov MM, Chernomordik LV, Millay DP. Myomaker and Myomerger Work Independently to Control Distinct Steps of Membrane Remodeling during Myoblast Fusion. Dev Cell 2018; 46:767-780.e7. [PMID: 30197239 DOI: 10.1016/j.devcel.2018.08.006] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/27/2018] [Accepted: 08/08/2018] [Indexed: 02/03/2023]
Abstract
Classic mechanisms for membrane fusion involve transmembrane proteins that assemble into complexes and dynamically alter their conformation to bend membranes, leading to mixing of membrane lipids (hemifusion) and fusion pore formation. Myomaker and Myomerger govern myoblast fusion and muscle formation but are structurally divergent from traditional fusogenic proteins. Here, we show that Myomaker and Myomerger independently mediate distinct steps in the fusion pathway, where Myomaker is involved in membrane hemifusion and Myomerger is necessary for fusion pore formation. Mechanistically, we demonstrate that Myomerger is required on the cell surface where its ectodomains stress membranes. Moreover, we show that Myomerger drives fusion completion in a heterologous system independent of Myomaker and that a Myomaker-Myomerger physical interaction is not required for function. Collectively, our data identify a stepwise cell fusion mechanism in myoblasts where different proteins are delegated to perform unique membrane functions essential for membrane coalescence.
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Affiliation(s)
- Evgenia Leikina
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dilani G Gamage
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Vikram Prasad
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Joanna Goykhberg
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael Crowe
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Jiajie Diao
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Leonid V Chernomordik
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Douglas P Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
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29
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Liu Z, Wang C, Liu X, Kuang S. Shisa2 regulates the fusion of muscle progenitors. Stem Cell Res 2018; 31:31-41. [PMID: 30007221 PMCID: PMC6171505 DOI: 10.1016/j.scr.2018.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 06/25/2018] [Accepted: 07/05/2018] [Indexed: 11/21/2022] Open
Abstract
Adult skeletal muscles are comprised of multinuclear muscle cells called myofibers. During skeletal muscle development and regeneration, mononuclear progenitor cells (myoblasts) fuse to form multinuclear myotubes, which mature and become myofibers. The molecular events mediating myoblast fusion are not fully understood. Here we report that Shisa2, an endoplasmic reticulum (ER) localized protein, regulates the fusion of muscle satellite cell-derived primary myoblasts. Shisa2 expression is repressed by Notch signaling, elevated in activated compared to quiescent satellite cells, and further upregulated during myogenic differentiation. Knockdown of Shisa2 inhibits the fusion of myoblasts without affecting proliferation. Conversely, Shisa2 overexpression in proliferating myoblasts inhibits their proliferation but promotes premature fusion. Interestingly, Shisa2-overexpressing nascent myotubes actively recruit myoblasts to fuse with. At the molecular level, Rac1/Cdc42-mediated cytoskeletal F-actin remodeling is required for Shisa2 to promote myoblast fusion. These results provide a novel mechanism through which an ER protein regulates myogenesis.
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Affiliation(s)
- Zuojun Liu
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA; Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA.
| | - Chao Wang
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Xiaoqi Liu
- Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA; Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Shihuan Kuang
- Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA; Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA.
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30
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Morris HT, Fort L, Spence HJ, Patel R, Vincent DF, Park JH, Snapper SB, Carey FA, Sansom OJ, Machesky LM. Loss of N-WASP drives early progression in an Apc model of intestinal tumourigenesis. J Pathol 2018; 245:337-348. [PMID: 29672847 PMCID: PMC6033012 DOI: 10.1002/path.5086] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/15/2018] [Accepted: 04/12/2018] [Indexed: 01/23/2023]
Abstract
N-WASP (WASL) is a widely expressed cytoskeletal signalling and scaffold protein also implicated in regulation of Wnt signalling and homeostatic maintenance of skin epithelial architecture. N-WASP mediates invasion of cancer cells in vitro and its depletion reduces invasion and metastatic dissemination of breast cancer. Given this role in cancer invasion and universal expression in the gastrointestinal tract, we explored a role for N-WASP in the initiation and progression of colorectal cancer. While deletion of N-wasp is not detectably harmful in the murine intestinal tract, numbers of Paneth cells increased, indicating potential changes in the stem cell niche, and migration up the crypt-villus axis was enhanced. Loss of N-wasp promoted adenoma formation in an adenomatous polyposis coli (Apc) deletion model of intestinal tumourigenesis. Thus, we establish a tumour suppressive role of N-WASP in early intestinal carcinogenesis despite its later pro-invasive role in other cancers. Our study highlights that while the actin cytoskeletal machinery promotes invasion of cancer cells, it also maintains normal epithelial tissue function and thus may have tumour suppressive roles in pre-neoplastic tissues. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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MESH Headings
- Adenomatous Polyposis Coli/genetics
- Adenomatous Polyposis Coli/metabolism
- Adenomatous Polyposis Coli/pathology
- Aged
- Animals
- Cell Differentiation
- Cell Movement
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Colon/metabolism
- Colon/pathology
- DNA Mismatch Repair
- Disease Models, Animal
- Disease Progression
- Female
- Genes, APC
- Genes, Tumor Suppressor
- Genetic Predisposition to Disease
- Humans
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Middle Aged
- Neoplasm Invasiveness
- Neoplastic Stem Cells/metabolism
- Neoplastic Stem Cells/pathology
- Paneth Cells/metabolism
- Paneth Cells/pathology
- Phenotype
- Stem Cell Niche
- Tumor Microenvironment
- Wiskott-Aldrich Syndrome Protein, Neuronal/deficiency
- Wiskott-Aldrich Syndrome Protein, Neuronal/genetics
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Affiliation(s)
| | - Loic Fort
- Cancer Research UK Beatson InstituteBearsden, GlasgowUK
| | | | - Rachana Patel
- Cancer Research UK Beatson InstituteBearsden, GlasgowUK
| | | | - James H Park
- Academic Unit of Surgery, School of Medicine, Dentistry and NursingUniversity of Glasgow, Glasgow Royal InfirmaryGlasgowUK
| | - Scott B Snapper
- Harvard Medical School and Boston Children's HospitalDivision of Gastroenterology, Hepatology and NutritionBostonMassachusettsUSA
| | | | - Owen J Sansom
- Cancer Research UK Beatson InstituteBearsden, GlasgowUK
- Institute of Cancer SciencesUniversity of GlasgowBearsden, GlasgowUK
| | - Laura M Machesky
- Cancer Research UK Beatson InstituteBearsden, GlasgowUK
- Institute of Cancer SciencesUniversity of GlasgowBearsden, GlasgowUK
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31
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Chaweewannakorn C, Tsuchiya M, Koide M, Hatakeyama H, Tanaka Y, Yoshida S, Sugawara S, Hagiwara Y, Sasaki K, Kanzaki M. Roles of IL-1α/β in regeneration of cardiotoxin-injured muscle and satellite cell function. Am J Physiol Regul Integr Comp Physiol 2018. [PMID: 29513560 DOI: 10.1152/ajpregu.00310.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Skeletal muscle regeneration after injury is a complex process involving interactions between inflammatory microenvironments and satellite cells. Interleukin (IL)-1 is a key mediator of inflammatory responses and exerts pleiotropic impacts on various cell types. Thus, we aimed to investigate the role of IL-1 during skeletal muscle regeneration. We herein show that IL-1α/β-double knockout (IL-1KO) mice exhibit delayed muscle regeneration after cardiotoxin (CTX) injection, characterized by delayed infiltrations of immune cells accompanied by suppressed local production of proinflammatory factors including IL-6 and delayed increase of paired box 7 (PAX7)-positive satellite cells postinjury compared with those of wild-type (WT) mice. A series of in vitro experiments using satellite cells obtained from the IL-1KO mice unexpectedly revealed that IL-1KO myoblasts have impairments in terms of both proliferation and differentiation, both of which were reversed by exogenous IL-1β administration in culture. Intriguingly, the delay in myogenesis was not attributable to the myogenic transcriptional program since MyoD and myogenin were highly upregulated in IL-1KO cells, instead appearing, at least in part, to be due to dysregulation of cellular fusion events, possibly resulting from aberrant actin regulatory systems. We conclude that IL-1 plays a positive role in muscle regeneration by coordinating the initial interactions among inflammatory microenvironments and satellite cells. Our findings also provide compelling evidence that IL-1 is intimately engaged in regulating the fundamental function of myocytes.
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Affiliation(s)
- Chayanit Chaweewannakorn
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry , Sendai , Japan.,Tohoku University Graduate School of Biomedical Engineering , Sendai , Japan
| | | | - Masashi Koide
- Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine , Sendai , Japan
| | - Hiroyasu Hatakeyama
- Tohoku University Graduate School of Biomedical Engineering , Sendai , Japan.,Frontier Research Institute for Interdisciplinary Science, Tohoku University , Sendai , Japan
| | - Yukinori Tanaka
- Division of Oral Immunology, Tohoku University Graduate School of Dentistry , Sendai , Japan
| | - Shinichirou Yoshida
- Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine , Sendai , Japan
| | - Shunji Sugawara
- Division of Oral Immunology, Tohoku University Graduate School of Dentistry , Sendai , Japan
| | - Yoshihiro Hagiwara
- Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine , Sendai , Japan
| | - Keiichi Sasaki
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry , Sendai , Japan
| | - Makoto Kanzaki
- Tohoku University Graduate School of Biomedical Engineering , Sendai , Japan
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32
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Kneppers A, Verdijk L, de Theije C, Corten M, Gielen E, van Loon L, Schols A, Langen R. A novel in vitro model for the assessment of postnatal myonuclear accretion. Skelet Muscle 2018; 8:4. [PMID: 29444710 PMCID: PMC5813369 DOI: 10.1186/s13395-018-0151-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 01/26/2018] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Due to the post-mitotic nature of myonuclei, postnatal myogenesis is essential for skeletal muscle growth, repair, and regeneration. This process is facilitated by satellite cells through proliferation, differentiation, and subsequent fusion with a pre-existing muscle fiber (i.e., myonuclear accretion). Current knowledge of myogenesis is primarily based on the in vitro formation of syncytia from myoblasts, which represents aspects of developmental myogenesis, but may incompletely portray postnatal myogenesis. Therefore, we aimed to develop an in vitro model that better reflects postnatal myogenesis, to study the cell intrinsic and extrinsic processes and signaling involved in the regulation of postnatal myogenesis. METHODS Proliferating C2C12 myoblasts were trypsinized and co-cultured for 3 days with 5 days differentiated C2C12 myotubes. Postnatal myonuclear accretion was visually assessed by live cell time-lapse imaging and cell tracing by cell labeling with Vybrant® DiD and DiO. Furthermore, a Cre/LoxP-based cell system was developed to semi-quantitatively assess in vitro postnatal myonuclear accretion by the conditional expression of luciferase upon myoblast-myotube fusion. Luciferase activity was assessed luminometrically and corrected for total protein content. RESULTS Live cell time-lapse imaging, staining-based cell tracing, and recombination-dependent luciferase activity, showed the occurrence of postnatal myonuclear accretion in vitro. Treatment of co-cultures with the myogenic factor IGF-I (p < 0.001) and the cytokines IL-13 (p < 0.05) and IL-4 (p < 0.001) increased postnatal myonuclear accretion, while the myogenic inhibitors cytochalasin D (p < 0.001), myostatin (p < 0.05), and TNFα (p < 0.001) decreased postnatal myonuclear accretion. Furthermore, postnatal myonuclear accretion was increased upon recovery from electrical pulse stimulation-induced fiber damage (p < 0.001) and LY29004-induced atrophy (p < 0.001). Moreover, cell type-specific siRNA-mediated knockdown of myomaker in myoblasts (p < 0.001), but not in myotubes, decreased postnatal myonuclear accretion. CONCLUSIONS We developed a physiologically relevant, sensitive, high-throughput cell system for semi-quantitative assessment of in vitro postnatal myonuclear accretion, which can be used to mimic physiological myogenesis triggers, and can distinguish the cell type-specific roles of signals and responses in the regulation of postnatal myogenesis. As such, this method is suitable for both basal and translational research on the regulation of postnatal myogenesis, and will improve our understanding of muscle pathologies that result from impaired satellite cell number or function.
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Affiliation(s)
- Anita Kneppers
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands.
| | - Lex Verdijk
- Department of Human Biology and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Chiel de Theije
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Mark Corten
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Ellis Gielen
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Luc van Loon
- Department of Human Biology and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Annemie Schols
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Ramon Langen
- Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
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33
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Sampath SC, Sampath SC, Millay DP. Myoblast fusion confusion: the resolution begins. Skelet Muscle 2018; 8:3. [PMID: 29386054 PMCID: PMC5793351 DOI: 10.1186/s13395-017-0149-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 12/29/2017] [Indexed: 02/06/2023] Open
Abstract
The fusion of muscle precursor cells is a required event for proper skeletal muscle development and regeneration. Numerous proteins have been implicated to function in myoblast fusion; however, the majority are expressed in diverse tissues and regulate numerous cellular processes. How myoblast fusion is triggered and coordinated in a muscle-specific manner has remained a mystery for decades. Through the discovery of two muscle-specific fusion proteins, Myomaker and Myomerger–Minion, we are now primed to make significant advances in our knowledge of myoblast fusion. This article reviews the latest findings regarding the biology of Myomaker and Minion–Myomerger, places these findings in the context of known pathways in mammalian myoblast fusion, and highlights areas that require further investigation. As our understanding of myoblast fusion matures so does our potential ability to manipulate cell fusion for therapeutic purposes.
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Affiliation(s)
- Srihari C Sampath
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, CA, 92121, USA. .,Division of Musculoskeletal Imaging, Department of Radiology, University of California San Diego School of Medicine, 200 West Arbor Drive, San Diego, CA, 92103, USA.
| | - Srinath C Sampath
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, CA, 92121, USA. .,Division of Musculoskeletal Imaging, Department of Radiology, University of California San Diego School of Medicine, 200 West Arbor Drive, San Diego, CA, 92103, USA.
| | - Douglas P Millay
- Department of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, 240 Albert Sabin Way, Cincinnati, OH, 45229, USA. .,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, 45229, USA.
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34
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Randrianarison-Huetz V, Papaefthymiou A, Herledan G, Noviello C, Faradova U, Collard L, Pincini A, Schol E, Decaux JF, Maire P, Vassilopoulos S, Sotiropoulos A. Srf controls satellite cell fusion through the maintenance of actin architecture. J Cell Biol 2017; 217:685-700. [PMID: 29269426 PMCID: PMC5800804 DOI: 10.1083/jcb.201705130] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 10/20/2017] [Accepted: 11/21/2017] [Indexed: 01/17/2023] Open
Abstract
This work describes a crucial role for the transcription factor Srf and F-actin scaffold to drive muscle stem cell fusion in vitro and in vivo and provides evidence of how actin cytoskeleton architecture affects myoblast fusion in vertebrates. Satellite cells (SCs) are adult muscle stem cells that are mobilized when muscle homeostasis is perturbed. Here, we show that serum response factor (Srf) is needed for optimal SC-mediated hypertrophic growth. We identified Srf as a master regulator of SC fusion required in both fusion partners, whereas it was dispensable for SC proliferation and differentiation. We show that SC-specific Srf deletion leads to impaired actin cytoskeleton and report the existence of finger-like actin–based protrusions at fusion sites in vertebrates that were notoriously absent in fusion-defective myoblasts lacking Srf. Restoration of a polymerized actin network by overexpression of an α-actin isoform in Srf mutant SCs rescued their fusion with a control cell in vitro and in vivo and reestablished overload-induced muscle growth. These findings demonstrate the importance of Srf in controlling the organization of actin cytoskeleton and actin-based protrusions for myoblast fusion in mammals and its requirement to achieve efficient hypertrophic myofiber growth.
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Affiliation(s)
- Voahangy Randrianarison-Huetz
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Aikaterini Papaefthymiou
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Gaëlle Herledan
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Chiara Noviello
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Ulduz Faradova
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | | | - Alessandra Pincini
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Emilie Schol
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Jean François Decaux
- Université Pierre et Marie Curie Paris 6, Centre National de la Recherche Scientifique UMR8256, Institut National de la Santé et de la Recherche Médicale U1164, Institute of Biology Paris-Seine, Paris, France
| | - Pascal Maire
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France.,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
| | - Stéphane Vassilopoulos
- Institut National de la Santé et de la Recherche Médicale/University Pierre and Marie Curie UMR-S974, Institut de Myologie, Paris, France
| | - Athanassia Sotiropoulos
- Institut National de la Santé et de la Recherche Médicale U1016, Institut Cochin, Paris, France .,Centre National de la Recherche Scientifique UMR8104, Paris, France.,Université Paris Descartes, Paris, France
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35
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Deng S, Azevedo M, Baylies M. Acting on identity: Myoblast fusion and the formation of the syncytial muscle fiber. Semin Cell Dev Biol 2017; 72:45-55. [PMID: 29101004 DOI: 10.1016/j.semcdb.2017.10.033] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 10/25/2017] [Accepted: 10/30/2017] [Indexed: 12/25/2022]
Abstract
The study of Drosophila muscle development dates back to the middle of the last century. Since that time, Drosophila has proved to be an ideal system for studying muscle development, differentiation, function, and disease. As in humans, Drosophila muscle forms via a series of conserved steps, starting with muscle specification, myoblast fusion, attachment to tendon cells, interactions with motorneurons, and sarcomere and myofibril formation. The genes and mechanisms required for these processes share striking similarities to those found in humans. The highly tractable genetic system and imaging approaches available in Drosophila allow for an efficient interrogation of muscle biology and for application of what we learn to other systems. In this article, we review our current understanding of muscle development in Drosophila, with a focus on myoblast fusion, the process responsible for the generation of syncytial muscle cells. We also compare and contrast those genes required for fusion in Drosophila and vertebrates.
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Affiliation(s)
- Su Deng
- Program in Developmental Biology, Sloan Kettering Institute, New York, NY 10065, United States
| | - Mafalda Azevedo
- Program in Developmental Biology, Sloan Kettering Institute, New York, NY 10065, United States; Graduate Program in Basic and Applied Biology (GABBA), Institute of Biomedical Sciences Abel Salazar, University of Porto, Porto, Portugal
| | - Mary Baylies
- Program in Developmental Biology, Sloan Kettering Institute, New York, NY 10065, United States.
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36
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Shin JY, Méndez-López I, Hong M, Wang Y, Tanji K, Wu W, Shugol L, Krauss RS, Dauer WT, Worman HJ. Lamina-associated polypeptide 1 is dispensable for embryonic myogenesis but required for postnatal skeletal muscle growth. Hum Mol Genet 2017; 26:65-78. [PMID: 27798115 DOI: 10.1093/hmg/ddw368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 10/21/2016] [Indexed: 12/17/2022] Open
Abstract
Lamina-associated polypeptide 1 (LAP1) is an integral protein of the inner nuclear membrane that has been implicated in striated muscle maintenance. Mutations in its gene have been linked to muscular dystrophy and cardiomyopathy. As germline deletion of the gene encoding LAP1 is perinatal lethal, we explored its potential role in myogenic differentiation and development by generating a conditional knockout mouse in which the protein is depleted from muscle progenitors at embryonic day 8.5 (Myf5-Lap1CKO mice). Although cultured myoblasts lacking LAP1 demonstrated defective terminal differentiation and altered expression of muscle regulatory factors, embryonic myogenesis and formation of skeletal muscle occurred in both mice with a Lap1 germline deletion and Myf5-Lap1CKO mice. However, skeletal muscle fibres were hypotrophic and their nuclei were morphologically abnormal with a wider perinuclear space than normal myonuclei. Myf5-Lap1CKO mouse skeletal muscle contained fewer satellite cells than normal and these cells had evidence of reduced myogenic potential. Abnormalities in signalling pathways required for postnatal hypertrophic growth were also observed in skeletal muscles of these mice. Our results demonstrate that early embryonic depletion of LAP1 does not impair myogenesis but that it is necessary for postnatal skeletal muscle growth.
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Affiliation(s)
- Ji-Yeon Shin
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Iván Méndez-López
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Mingi Hong
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yuexia Wang
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Kurenai Tanji
- Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Wei Wu
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Leana Shugol
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
| | - Robert S Krauss
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - William T Dauer
- Department of Neurology.,Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Howard J Worman
- Department of Medicine.,Department of Pathology and Cell Biology, College of Physicians & Surgeons, Columbia University, New York, NY, USA
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37
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Tunduguru R, Zhang J, Aslamy A, Salunkhe VA, Brozinick JT, Elmendorf JS, Thurmond DC. The actin-related p41ARC subunit contributes to p21-activated kinase-1 (PAK1)-mediated glucose uptake into skeletal muscle cells. J Biol Chem 2017; 292:19034-19043. [PMID: 28972183 DOI: 10.1074/jbc.m117.801340] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/21/2017] [Indexed: 02/04/2023] Open
Abstract
Defects in translocation of the glucose transporter GLUT4 are associated with peripheral insulin resistance, preclinical diabetes, and progression to type 2 diabetes. GLUT4 recruitment to the plasma membrane of skeletal muscle cells requires F-actin remodeling. Insulin signaling in muscle requires p21-activated kinase-1 (PAK1), whose downstream signaling triggers actin remodeling, which promotes GLUT4 vesicle translocation and glucose uptake into skeletal muscle cells. Actin remodeling is a cyclic process, and although PAK1 is known to initiate changes to the cortical actin-binding protein cofilin to stimulate the depolymerizing arm of the cycle, how PAK1 might trigger the polymerizing arm of the cycle remains unresolved. Toward this, we investigated whether PAK1 contributes to the mechanisms involving the actin-binding and -polymerizing proteins neural Wiskott-Aldrich syndrome protein (N-WASP), cortactin, and ARP2/3 subunits. We found that the actin-polymerizing ARP2/3 subunit p41ARC is a PAK1 substrate in skeletal muscle cells. Moreover, co-immunoprecipitation experiments revealed that insulin stimulates p41ARC phosphorylation and increases its association with N-WASP coordinately with the associations of N-WASP with cortactin and actin. Importantly, all of these associations were ablated by the PAK inhibitor IPA3, suggesting that PAK1 activation lies upstream of these actin-polymerizing complexes. Using the N-WASP inhibitor wiskostatin, we further demonstrated that N-WASP is required for localized F-actin polymerization, GLUT4 vesicle translocation, and glucose uptake. These results expand the model of insulin-stimulated glucose uptake in skeletal muscle cells by implicating p41ARC as a new component of the insulin-signaling cascade and connecting PAK1 signaling to N-WASP-cortactin-mediated actin polymerization and GLUT4 vesicle translocation.
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Affiliation(s)
- Ragadeepthi Tunduguru
- From the Departments of Biochemistry and Molecular Biology and.,the Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute and Beckman Research Institute of the City of Hope, Duarte, California 91010, and
| | - Jing Zhang
- the Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute and Beckman Research Institute of the City of Hope, Duarte, California 91010, and
| | - Arianne Aslamy
- the Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute and Beckman Research Institute of the City of Hope, Duarte, California 91010, and.,Cellular and Integrative Physiology, Center for Diabetes and Metabolic Diseases,Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Vishal A Salunkhe
- the Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute and Beckman Research Institute of the City of Hope, Duarte, California 91010, and
| | | | - Jeffrey S Elmendorf
- From the Departments of Biochemistry and Molecular Biology and.,Cellular and Integrative Physiology, Center for Diabetes and Metabolic Diseases,Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Debbie C Thurmond
- From the Departments of Biochemistry and Molecular Biology and .,the Department of Molecular and Cellular Endocrinology, Diabetes and Metabolism Research Institute and Beckman Research Institute of the City of Hope, Duarte, California 91010, and.,Cellular and Integrative Physiology, Center for Diabetes and Metabolic Diseases,Indiana University School of Medicine, Indianapolis, Indiana 46202
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38
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Zhang Y, Yang Y, Zhu Z, Ou G. WASP-Arp2/3-dependent actin polymerization influences fusogen localization during cell-cell fusion in Caenorhabditiselegans embryos. Biol Open 2017; 6:1324-1328. [PMID: 28760733 PMCID: PMC5612239 DOI: 10.1242/bio.026807] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Cell-cell fusion is essential for development and physiology. Actin polymerization was implicated in the Caenorhabditiselegans fusogen EFF-1 engagement in a reconstituted Drosophila cell culture system, and the actin-binding protein spectraplakin links EFF-1 to the actin cytoskeleton and promotes cell-cell fusions in C. elegans larvae. However, it remains unclear whether and how fusogens and the actin cytoskeleton are coordinated in C. elegans embryos. Here, we used live imaging analysis of GFP knock-in and RNAi embryos to study the embryonic cell-cell fusions in C. elegans. Our results show that the inhibition of WASP-Arp2/3-dependent actin polymerization delays cell-cell fusions. EFF-1 is primarily distributed in intracellular vesicles in embryonic fusing cells, and we find that the perturbation of actin polymerization reduces the number of EFF-1-postive vesicles. Thus, the actin cytoskeleton differently promotes cell-cell fusion by regulating fusogen localization to the fusing plasma membrane in larvae or to intracellular vesicles in embryos. Summary: WASP-Arp2/3 regulates fusogen localization to intracellular vesicles in C. elegans embryos. Our results indicate that cell-cell fusions rely on distinct mechanisms at different developmental stages.
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Affiliation(s)
- Yan Zhang
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
| | - Yihong Yang
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
| | - Zhiwen Zhu
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
| | - Guangshuo Ou
- Tsinghua-Peking Center for Life Sciences, School of Life Sciences and MOE Key Laboratory for Protein Science, Tsinghua University, Beijing 100084, China
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39
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Kalailingam P, Tan HB, Jain N, Sng MK, Chan JSK, Tan NS, Thanabalu T. Conditional knock out of N-WASP in keratinocytes causes skin barrier defects and atopic dermatitis-like inflammation. Sci Rep 2017; 7:7311. [PMID: 28779153 PMCID: PMC5544743 DOI: 10.1038/s41598-017-07125-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 06/22/2017] [Indexed: 01/11/2023] Open
Abstract
Neural-Wiskott Aldrich Syndrome Protein (N-WASP) is expressed ubiquitously and regulates actin cytoskeleton remodeling. In order to characterize the role of N-WASP in epidermal homeostasis and cutaneous biology, we generated conditional N-WASP knockout mouse using CK14-cre (cytokeratin 14) to ablate expression of N-WASP in keratinocytes. N-WASPK14KO (N-WASPfl/fl; CK14-Cre) mice were born following Mendelian genetics suggesting that N-WASP expression in keratinocytes is not essential during embryogenesis. N-WASPK14KO mice exhibited stunted growth, alopecia, dry and wrinkled skin. The dry skin in N-WASPK14KO mice is probably due to increased transepidermal water loss (TEWL) caused by barrier function defects as revealed by dye penetration assay. N-WASPK14KO mice developed spontaneous inflammation in the neck and face 10 weeks after birth. Histological staining revealed thickening of the epidermis, abnormal cornified layer and extensive infiltration of immune cells (mast cells, eosinophils and T-lymphocytes) in N-WASPK14KO mice skin compared to control mice. N-WASPK14KO mice had higher serum levels of IL-1α, TNF-α, IL-6 and IL-17 compared to control mice. Thus our results suggest that conditional N-WASP knockout in keratinocytes leads to compromised skin barrier, higher infiltration of immune cells and hyperproliferation of keratinocytes due to increased production of cytokines highlighting the importance of N-WASP in maintaining the skin homeostasis.
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Affiliation(s)
- Pazhanichamy Kalailingam
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Hui Bing Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Neeraj Jain
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Ming Keat Sng
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Avenue, Singapore, 636921, Republic of Singapore
| | - Jeremy Soon Kiat Chan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Avenue, Singapore, 636921, Republic of Singapore.,Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore, 138673, Republic of Singapore.,KK Women's and Children's Hospital, 100 Bukit Timah Road, Singapore, 229899, Republic of Singapore
| | - Thirumaran Thanabalu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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40
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Yang Y, Zhang Y, Li WJ, Jiang Y, Zhu Z, Hu H, Li W, Wu JW, Wang ZX, Dong MQ, Huang S, Ou G. Spectraplakin Induces Positive Feedback between Fusogens and the Actin Cytoskeleton to Promote Cell-Cell Fusion. Dev Cell 2017; 41:107-120.e4. [DOI: 10.1016/j.devcel.2017.03.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 01/18/2017] [Accepted: 03/10/2017] [Indexed: 10/25/2022]
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41
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Group I Paks Promote Skeletal Myoblast Differentiation In Vivo and In Vitro. Mol Cell Biol 2017; 37:MCB.00222-16. [PMID: 27920252 DOI: 10.1128/mcb.00222-16] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 11/26/2016] [Indexed: 12/15/2022] Open
Abstract
Skeletal myogenesis is regulated by signal transduction, but the factors and mechanisms involved are not well understood. The group I Paks Pak1 and Pak2 are related protein kinases and direct effectors of Cdc42 and Rac1. Group I Paks are ubiquitously expressed and specifically required for myoblast fusion in Drosophila We report that both Pak1 and Pak2 are activated during mammalian myoblast differentiation. One pathway of activation is initiated by N-cadherin ligation and involves the cadherin coreceptor Cdo with its downstream effector, Cdc42. Individual genetic deletion of Pak1 and Pak2 in mice has no overt effect on skeletal muscle development or regeneration. However, combined muscle-specific deletion of Pak1 and Pak2 results in reduced muscle mass and a higher proportion of myofibers with a smaller cross-sectional area. This phenotype is exacerbated after repair to acute injury. Furthermore, primary myoblasts lacking Pak1 and Pak2 display delayed expression of myogenic differentiation markers and myotube formation. These results identify Pak1 and Pak2 as redundant regulators of myoblast differentiation in vitro and in vivo and as components of the promyogenic Ncad/Cdo/Cdc42 signaling pathway.
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42
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Krauss RS, Joseph GA, Goel AJ. Keep Your Friends Close: Cell-Cell Contact and Skeletal Myogenesis. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a029298. [PMID: 28062562 DOI: 10.1101/cshperspect.a029298] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Development of skeletal muscle is a multistage process that includes lineage commitment of multipotent progenitor cells, differentiation and fusion of myoblasts into multinucleated myofibers, and maturation of myofibers into distinct types. Lineage-specific transcriptional regulation lies at the core of this process, but myogenesis is also regulated by extracellular cues. Some of these cues are initiated by direct cell-cell contact between muscle precursor cells themselves or between muscle precursors and cells of other lineages. Examples of the latter include interaction of migrating neural crest cells with multipotent muscle progenitor cells, muscle interstitial cells with myoblasts, and neurons with myofibers. Among the signaling factors involved are Notch ligands and receptors, cadherins, Ig superfamily members, and Ephrins and Eph receptors. In this article we describe recent progress in this area and highlight open questions raised by the findings.
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Affiliation(s)
- Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Giselle A Joseph
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Aviva J Goel
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029
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43
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Myogenic differentiation depends on the interplay of Grb2 and N-WASP. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:487-497. [PMID: 27965114 DOI: 10.1016/j.bbamcr.2016.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 12/02/2016] [Accepted: 12/09/2016] [Indexed: 12/19/2022]
Abstract
Myogenesis requires a well-coordinated withdrawal from cell cycle, morphological changes and cell fusion mediated by actin cytoskeleton. Grb2 is an adaptor protein whose central SH2 domain binds to phosphorylated tyrosine residues of activated receptors and activates intracellular signaling pathway, while its N-terminal and C-terminal SH3 domains bind to proline rich proteins such as N-WASP (Neural-Wiskott Aldrich Syndrome Protein). We found that the expression of Grb2 was increased at the beginning of differentiation and remained constant during differentiation in C2C12 myoblasts. Knocking down endogenous Grb2 expression caused a significant increase in the fusion index and expression of MyHC, a terminal differentiation marker when compared with the control. Over expression of Grb2 in C2C12 (C2C12Grb2-Myc) reduced myotube formation and expression of MyHC. Similarly over expression of Grb2P49L-Myc (N-terminal SH3 domain mutant) or Grb2R86K-Myc (SH2 domain mutant) inhibited myogenic differentiation of C2C12 cells. However, the expression of Grb2P206L-Myc (C-terminal SH3 domain mutant) did not inhibit myotube formation and expression of MyHC. This suggests that the C-terminal SH3 domain of Grb2 is critical for the inhibition of myogenic differentiation. The C2C12Grb2-Myc cells have reduced phalloidin staining at late stages of differentiation. Expression of N-WASP in C2C12Grb2-Myc cells rescued the myogenic defect and increased phalloidin staining (increased F-actin) in these cells. Thus our results suggest that Grb2 is a negative regulator of myogenesis and reduces myogenic differentiation by inhibiting actin polymerization/remodeling through its C-terminal SH3 domain.
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44
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Jain N, Kalailingam P, Tan KW, Tan HB, Sng MK, Chan JSK, Tan NS, Thanabalu T. Conditional knockout of N-WASP in mouse fibroblast caused keratinocyte hyper proliferation and enhanced wound closure. Sci Rep 2016; 6:38109. [PMID: 27909303 PMCID: PMC5133560 DOI: 10.1038/srep38109] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 11/04/2016] [Indexed: 12/15/2022] Open
Abstract
Neural-Wiskott Aldrich Syndrome Protein (N-WASP) is expressed ubiquitously, regulates actin polymerization and is essential during mouse development. We have previously shown that N-WASP is critical for cell-ECM adhesion in fibroblasts. To characterize the role of N-WASP in fibroblast for skin development, we generated a conditional knockout mouse model in which fibroblast N-WASP was ablated using the Cre recombinase driven by Fibroblast Specific Protein promoter (Fsp-Cre). N-WASPFKO (N-WASPfl/fl; Fsp-cre) were born following Mendelian genetics, survived without any visible abnormalities for more than 1 year and were sexually reproductive, suggesting that expression of N-WASP in fibroblast is not critical for survival under laboratory conditions. Histological sections of N-WASPFKO mice skin (13 weeks old) showed thicker epidermis with higher percentage of cells staining for proliferation marker (PCNA), suggesting that N-WASP deficient fibroblasts promote keratinocyte proliferation. N-WASPFKO mice skin had elevated collagen content, elevated expression of FGF7 (keratinocyte growth factor) and TGFβ signaling proteins. Wound healing was faster in N-WASPFKO mice compared to control mice and N-WASP deficient fibroblasts were found to have enhanced collagen gel contraction properties. These results suggest that N-WASP deficiency in fibroblasts improves wound healing by growth factor-mediated enhancement of keratinocyte proliferation and increased wound contraction in mice.
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Affiliation(s)
- Neeraj Jain
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Pazhanichamy Kalailingam
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Kai Wei Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Hui Bing Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Ming Keat Sng
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Jeremy Soon Kiat Chan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
| | - Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore.,Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Agency for Science Technology &Research, 138673, Singapore.,KK Research Centre, KK Women's and Children's Hospital, 100 Bukit Timah Road, 229899, Singapore
| | - Thirumaran Thanabalu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Republic of Singapore
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45
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Schejter ED. Myoblast fusion: Experimental systems and cellular mechanisms. Semin Cell Dev Biol 2016; 60:112-120. [DOI: 10.1016/j.semcdb.2016.07.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 07/11/2016] [Accepted: 07/12/2016] [Indexed: 12/18/2022]
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46
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Role and organization of the actin cytoskeleton during cell-cell fusion. Semin Cell Dev Biol 2016; 60:121-126. [PMID: 27476112 DOI: 10.1016/j.semcdb.2016.07.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 11/23/2022]
Abstract
Cell-cell fusion is a ubiquitous process that underlies fertilization and development of eukaryotes. This process requires fusogenic machineries to promote plasma membrane merging, and also relies on the organization of dedicated sub-cortical cytoskeletal assemblies. This review describes the role of actin structures, so called actin fusion foci, essential for the fusion of two distinct cell types: Drosophila myoblast cells, which fuse to form myotubes, and sexually differentiated cells of the fission yeast Schizosaccharomyces pombe, which fuse to form a zygote. I describe the respective composition and organization of the two structures, discuss their proposed role in promoting plasma membrane apposition, and consider the universality of similar structures for cell-cell fusion.
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47
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Deng S, Bothe I, Baylies M. Diaphanous regulates SCAR complex localization during Drosophila myoblast fusion. Fly (Austin) 2016; 10:178-86. [PMID: 27314572 DOI: 10.1080/19336934.2016.1195938] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
From Drosophila to man, multinucleated muscle cells form through cell-cell fusion. Using Drosophila as a model system, researchers first identified, and then demonstrated, the importance of actin cytoskeletal rearrangements at the site of fusion. These actin rearrangements at the fusion site are regulated by SCAR and WASp mediated Arp2/3 activation, which nucleates branched actin networks. Loss of SCAR, WASp or both leads to defects in myoblast fusion. Recently, we have found that the actin regulator Diaphanous (Dia) also plays a role both in organizing actin and in regulating Arp2/3 activity at the fusion site. In this Extra View article, we provide additional data showing that the Abi-SCAR complex accumulates at the fusion site and that excessive SCAR activity impairs myoblast fusion. Using constitutively active Dia constructs, we provide additional evidence that Dia functions upstream of SCAR activity to regulate actin dynamics at the fusion site and to localize the Abi-SCAR complex.
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Affiliation(s)
- Su Deng
- a Graduate Program in Physiology , Biophysics & Systems Biology, Weill Cornell Graduate School of Medical Sciences, Cornell University , New York , NY , USA
| | - Ingo Bothe
- b Program in Developmental Biology , Sloan Kettering Institute , New York , NY , USA
| | - Mary Baylies
- a Graduate Program in Physiology , Biophysics & Systems Biology, Weill Cornell Graduate School of Medical Sciences, Cornell University , New York , NY , USA.,b Program in Developmental Biology , Sloan Kettering Institute , New York , NY , USA
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Poosala P, Ichinose H, Kitaoka T. Spatial Geometries of Self-Assembled Chitohexaose Monolayers Regulate Myoblast Fusion. Int J Mol Sci 2016; 17:ijms17050686. [PMID: 27164094 PMCID: PMC4881512 DOI: 10.3390/ijms17050686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 04/28/2016] [Accepted: 05/03/2016] [Indexed: 01/31/2023] Open
Abstract
Myoblast fusion into functionally-distinct myotubes to form in vitro skeletal muscle constructs under differentiation serum-free conditions still remains a challenge. Herein, we report that our microtopographical carbohydrate substrates composed of bioactive hexa-N-acetyl-d-glucosamine (GlcNAc6) modulated the efficiency of myoblast fusion without requiring horse serum or any differentiation medium during cell culture. Promotion of the differentiation of dissociated mononucleated skeletal myoblasts (C2C12; a mouse myoblast cell line) into robust myotubes was found only on GlcNAc6 micropatterns, whereas the myoblasts on control, non-patterned GlcNAc6 substrates or GlcNAc6-free patterns exhibited an undifferentiated form. We also examined the possible role of GlcNAc6 micropatterns with various widths in the behavior of C2C12 cells in early and late stages of myogenesis through mRNA expression of myosin heavy chain (MyHC) isoforms. The spontaneous contraction of myotubes was investigated via the regulation of glucose transporter type 4 (GLUT4), which is involved in stimulating glucose uptake during cellular contraction. Narrow patterns demonstrated enhanced glucose uptake rate and generated a fast-twitch muscle fiber type, whereas the slow-twitch muscle fiber type was dominant on wider patterns. Our findings indicated that GlcNAc6-mediated integrin interactions are responsible for guiding myoblast fusion forward along with myotube formation.
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Affiliation(s)
- Pornthida Poosala
- Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
| | - Hirofumi Ichinose
- Faculty of Agriculture, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
| | - Takuya Kitaoka
- Faculty of Agriculture, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
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Structure-function analysis of myomaker domains required for myoblast fusion. Proc Natl Acad Sci U S A 2016; 113:2116-21. [PMID: 26858401 DOI: 10.1073/pnas.1600101113] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
During skeletal muscle development, myoblasts fuse to form multinucleated myofibers. Myomaker [Transmembrane protein 8c (TMEM8c)] is a muscle-specific protein that is essential for myoblast fusion and sufficient to promote fusion of fibroblasts with muscle cells; however, the structure and biochemical properties of this membrane protein have not been explored. Here, we used CRISPR/Cas9 mutagenesis to disrupt myomaker expression in the C2C12 muscle cell line, which resulted in complete blockade to fusion. To define the functional domains of myomaker required to direct fusion, we established a heterologous cell-cell fusion system, in which fibroblasts expressing mutant versions of myomaker were mixed with WT myoblasts. Our data indicate that the majority of myomaker is embedded in the plasma membrane with seven membrane-spanning regions and a required intracellular C-terminal tail. We show that myomaker function is conserved in other mammalian orthologs; however, related family members (TMEM8a and TMEM8b) do not exhibit fusogenic activity. These findings represent an important step toward deciphering the cellular components and mechanisms that control myoblast fusion and muscle formation.
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Dhanyasi N, Segal D, Shimoni E, Shinder V, Shilo BZ, VijayRaghavan K, Schejter ED. Surface apposition and multiple cell contacts promote myoblast fusion in Drosophila flight muscles. J Cell Biol 2016; 211:191-203. [PMID: 26459604 PMCID: PMC4602036 DOI: 10.1083/jcb.201503005] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Transmission EM methods reveal that cell–cell fusion of individual myoblasts with growing Drosophila flight muscles is a stepwise process in which the cell adhesion and branched actin machineries mediate tight apposition and formation of multiple contacts and pores between the surfaces of the fusing cells. Fusion of individual myoblasts to form multinucleated myofibers constitutes a widely conserved program for growth of the somatic musculature. We have used electron microscopy methods to study this key form of cell–cell fusion during development of the indirect flight muscles (IFMs) of Drosophila melanogaster. We find that IFM myoblast–myotube fusion proceeds in a stepwise fashion and is governed by apparent cross talk between transmembrane and cytoskeletal elements. Our analysis suggests that cell adhesion is necessary for bringing myoblasts to within a minimal distance from the myotubes. The branched actin polymerization machinery acts subsequently to promote tight apposition between the surfaces of the two cell types and formation of multiple sites of cell–cell contact, giving rise to nascent fusion pores whose expansion establishes full cytoplasmic continuity. Given the conserved features of IFM myogenesis, this sequence of cell interactions and membrane events and the mechanistic significance of cell adhesion elements and the actin-based cytoskeleton are likely to represent general principles of the myoblast fusion process.
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Affiliation(s)
- Nagaraju Dhanyasi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, Karnataka 560065, India Manipal University, Manipal, Karnataka 576104, India
| | - Dagan Segal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Eyal Shimoni
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Vera Shinder
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ben-Zion Shilo
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - K VijayRaghavan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, Karnataka 560065, India
| | - Eyal D Schejter
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
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