title: Spatio-temporal coordination of cell cycle exit, fusion and differentiation of adult muscle precursors by Drosophila Erect wing (Ewg).
abstract: The mechanisms of cell cycle exit by myoblasts during skeletal muscle development are poorly understood. Cell cycle arrest is known to be a prerequisite for myoblast fusion and subsequent differentiation. Despite tremendous knowledge on myoblast fusion and differentiation, tissue-specific factors that spatio-temporally regulate the cell cycle exit are not well known. In this paper, we show that the transcriptional factor/co-activator "Erect wing" (Ewg) synchronises myoblast cell cycle exit with that of the fusion process. Ewg-null myoblasts show delayed temporal development of dorsal longitudinal muscles (DLMs), a group of indirect flight muscles (IFMs), which culminates to abnormal and asymmetric muscle pattern. A role for Ewg in cell cycle exit at G1/S stage is also shown. Reducing Cyclin E dose in Ewg-null mutant rescues the lack of IFMs and flight ability. Thus, we show that Ewg repression of Cyclin E expression is required for the arrest of myoblast proliferation and initiate myoblast fusion and terminal differentiation.
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560 012, India.
authors.forename: Mamta
authors.initials: M
authors.lastname: Rai
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560 012, India.
authors.forename: Prasanna
authors.initials: P
authors.lastname: Katti
authors.affiliation: Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore 560 012, India. Electronic address: upendra@mrdg.iisc.ernet.in.
authors.forename: Upendra
authors.initials: U
authors.lastname: Nongthomba
mesh_terms: D000818:Animals; D059447:Cell Cycle Checkpoints / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D019927:Cyclin E / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development*; D024510:Muscle Development / Q000235:genetics; D032446:Myoblasts / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*; D014921:Wings, Animal / Q000254:growth & development* / Q000378:metabolism
chemical_list: D019927:Cyclin E; D029721:Drosophila Proteins; C081334:EWG protein, Drosophila; D009479:Neuropeptides; D014157:Transcription Factors
keywords: Cyclin E; Drosophila; Erect wing; Muscle development; NRF-1