A role for the Myoblast city homologues Dock1 and Dock5 and the adaptor proteins Crk and Crk-like in zebrafish myoblast fusion.
Myoblast fusion follows a defined sequence of events that is strikingly similar in vertebrates and invertebrates. Genetic analysis in Drosophila has identified many of the molecules that mediate the different steps in the fusion process; by contrast, the molecular basis of myoblast fusion during vertebrate embryogenesis remains poorly characterised. A key component of the intracellular fusion pathway in Drosophila is the protein encoded by the myoblast city (mbc) gene, a close homologue of the vertebrate protein dedicator of cytokinesis 1 (DOCK1, formerly DOCK180). Using morpholino antisense-oligonucleotide-mediated knockdown of gene activity in the zebrafish embryo, we show that the fusion of embryonic fast-twitch myoblasts requires the activities of Dock1 and the closely related Dock5 protein. In addition, we show that the adaptor proteins Crk and Crk-like (Crkl), with which Dock proteins are known to interact physically, are also required for myoblast fusion.
MRC Centre for Developmental and Biomedical Genetics, Department of Biomedical Science, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.
Catherine A
CA
Moore
Caroline A
CA
Parkin
Yannick
Y
Bidet
Philip W
PW
Ingham
D048868:Adaptor Proteins, Signal Transducing / Q000502:physiology*; D000818:Animals; D002459:Cell Fusion; D003001:Cloning, Molecular; D003598:Cytoskeletal Proteins / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D004625:Embryo, Nonmammalian; D024510:Muscle Development / Q000235:genetics*; D018656:Muscle Fibers, Fast-Twitch / Q000166:cytology; D032448:Myoblasts, Skeletal / Q000502:physiology; D009687:Nuclear Proteins / Q000502:physiology*; D050736:Oncogene Protein v-crk / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D015027:Zebrafish / Q000196:embryology* / Q000235:genetics* / Q000502:physiology; D029961:Zebrafish Proteins / Q000235:genetics / Q000502:physiology*; D020744:rac GTP-Binding Proteins
D048868:Adaptor Proteins, Signal Transducing; C082869:CRKL protein; D003598:Cytoskeletal Proteins; C524050:Dock1 protein, zebrafish; C524051:Dock5 protein, zebrafish; D029721:Drosophila Proteins; D009687:Nuclear Proteins; D050736:Oncogene Protein v-crk; D029961:Zebrafish Proteins; C107441:mbc protein, Drosophila; D020744:rac GTP-Binding Proteins