Dynamic Control of Cell Cycle and Growth Coupling by Ecdysone, EGFR, and PI3K Signaling in Drosophila Histoblasts

• DOI: 10.1371/journal.pbio.1000079
• Publication Date: 2009-04-03T17:16:27Z
• Authors: Nikolay Ninov; Cristina Manjón; Enrique Martín-Bl...
• Keywords: Cdc25

Regulation of cell proliferation has been extensively studied in cultured systems that are characterized by coordinated growth and cell-cycle progression relatively uniform size distribution. During the development multicellular organisms, however, division can be temporally uncoupled, signaling pathways regulate these programs poorly understood. A good model for analyzing control such is morphogenesis Drosophila adult abdominal epidermis histoblasts. These cells undergo a series regulated transitions during which neither nor rate constant. The histoblasts metamorphosis uniquely amenable to clonal analysis combination with live imaging. Thereby, we show histoblasts, grow while G2 arrest larval stages, enter proliferative stage pupal period initiated ecdysone-dependent string/Cdc25 phosphatase transcription. proliferating have preaccumulated stores Cyclin E, trigger an immediate S phase onset after mitosis. rapid cycles lack G1 result progressive reduction size. Eventually, proceed slower that, contrast preceding, depends on epidermal factor receptor (EGFR) through G2/M transition insulin receptor/PI3K-mediated growth. results uncover developmentally programmed changes coupling form Drosophila. Histoblasts three distinct stages: without division, growth, growth-coupled proliferation. Our identification regulators illustrates power vivo time-lapse analyses clone induction. It sets comprehensive understanding coordination complex eukaryotes.