Cell cycle genes regulate vestigial and scalloped to ensure normal proliferation in the wing disc of Drosophila melanogaster.
In Drosophila, the Vestigial-Scalloped (VG-SD) dimeric transcription factor is required for wing cell identity and proliferation. Previous results have shown that VG-SD controls expression of the cell cycle positive regulator dE2F1 during wing development. Since wing disc growth is a homeostatic process, we investigated the possibility that genes involved in cell cycle progression regulate vg and sd expression in feedback loops. We focused our experiments on two major regulators of cell cycle progression: dE2F1 and the antagonist dacapo (dap). Our results reinforce the idea that VG/SD stoichiometry is critical for correct development and that an excess in SD over VG disrupts wing growth. We reveal that transcriptional activity of VG-SD and the VG/SD ratio are both modulated by down-expression of cell cycle genes. We also detected a dap-induced sd up-regulation that disrupts wing growth. Moreover, we observed a rescue of a vg hypomorphic mutant phenotype by dE2F1 that is concomitant with vg and sd induction. This regulation of the VG-SD activity by dE2F1 is dependent on the vg genetic background. Our results support the hypothesis that cell cycle genes fine-tune wing growth and cell proliferation, in part, through control of the VG/SD stoichiometry and activity. This points to a homeostatic feedback regulation between proliferation regulators and the VG-SD wing selector.
Legent
Kevin
K
Institut Jacques Monod, CNRS UMR 7592, Universités Paris 6/Paris 7, Tour 43, 2 place Jussieu, 75251 Paris, cedex 05, France.
Dutriaux
Annie
A
Delanoue
Rénald
R
Silber
Joël
J
D000818:Animals; D049109:Cell Proliferation; D004330:Drosophila / Q000196:embryology*; D029721:Drosophila Proteins / Q000378:metabolism*; D050687:E2F1 Transcription Factor / Q000378:metabolism; D025461:Feedback, Physiological; D005786:Gene Expression Regulation; D018816:Genes, cdc / Q000502:physiology*; D006706:Homeostasis / Q000235:genetics; D050505:Mutant Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation; D014162:Transfection; D014921:Wings, Animal / Q000196:embryology* / Q000254:growth & development
D029721:Drosophila Proteins; D050687:E2F1 Transcription Factor; D050505:Mutant Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; C103336:dap protein, Drosophila; C087984:sd protein, Drosophila; C095064:vg protein, Drosophila