title: The Drosophila Chmp1 protein determines wing cell fate through regulation of epidermal growth factor receptor signaling.
abstract: BACKGROUND
  Receptor down-regulation by the multivesicular body (MVB) pathway is critical for many cellular signaling events. MVB generation is mediated by the highly conserved ESCRT (0, I, II, and III) protein complexes. Chmp1 is an ESCRT-III component and a putative tumor suppressor in humans. However, published data on Chmp1 activity are conflicting and its role during tissue development is not well defined.
  
  
  RESULTS
  We investigated the function of Drosophila Chmp1 and found that it is an essential gene. In the wing, loss of Chmp1 activity causes a cell fate change from intervein to vein, and interactions between Chmp1 and Drosophila Epidermal Growth Factor Receptor (DER) regulators suggest that Chmp1 negatively regulates DER signaling. Chmp1 knockdown also decreases Blistered expression, which is repressed by DER signaling. We find that Chmp1 protein localizes to the late endosome in Drosophila embryos, which is consistent with its effects on DER signaling resulting from its function in the ESCRT-III complex.
  
  
  CONCLUSIONS
  Drosophila Chmp1 negatively regulates DER signaling, likely through its role in MVB formation. Loss of Chmp1 activity in the Drosophila wing induces a cell fate change from intervein to vein that should provide a useful tool for future studies of ESCRT protein activity.
authors.affiliation: Department of Biomedical Sciences, Marshall University, Huntington, West Virginia.
authors.forename: Meagan
authors.initials: M
authors.lastname: Valentine
authors.forename: Justin
authors.initials: J
authors.lastname: Hogan
authors.forename: Simon
authors.initials: S
authors.lastname: Collier
mesh_terms: D000818:Animals; D004330:Drosophila / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D014921:Wings, Animal / Q000166:cytology / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D066246:ErbB Receptors
keywords: DER; EGFR; ESCRT; multivesicular body