title: Mal/SRF is dispensable for cell proliferation in Drosophila.
abstract: The Mal/SRF transcription factor is regulated by the level of G-actin in cells and has important roles in cell migration and other actin-dependent processes in Drosophila. A recent report suggests that Mal/SRF and an upstream regulator, Pico, are required for cell proliferation and tissue growth in Drosophila. I find otherwise. Mutation of Mal or SRF does not affect cell proliferation in the fly wing. Furthermore, I cannot reproduce the reported effects of Pico RNAi or Pico overexpression on body size. Nevertheless, I can confirm that overexpression of Pico or Mal causes tissue overgrowth specifically in the fly wing--where SRF is most highly expressed. My results indicate that Mal/SRF can promote tissue growth when abnormally active, but is not normally required for tissue growth during development.
authors.affiliation: Cancer Research UK, London Research Institute, London, United Kingdom. barry.thompson@cancer.org.uk
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Thompson
mesh_terms: D000818:Animals; D049628:Body Size; D049109:Cell Proliferation; D004330:Drosophila / Q000254:growth & development*; D029721:Drosophila Proteins / Q000502:physiology; D009154:Mutation; D026362:Serum Response Factor / Q000235:genetics / Q000502:physiology*; D014921:Wings, Animal / Q000166:cytology
chemical_list: D029721:Drosophila Proteins; C533183:Pico protein, Drosophila; D026362:Serum Response Factor
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