Translational control of <i>E2f1</i> regulates the <i>Drosophila</i> cell cycle
Jan Inge Øvrebø, Mary-Rose Bradley-Gill, Norman Zielke, Minhee Kim, Marco Marchetti, Jonathan Bohlen, Mitchell R. Lewis, Monique van Straaten, Nam-Sung Moon, Bruce A. Edgar
Abstract
Significance Here, we explore a mechanism wherein the growth signaling-dependent translation of mRNA encoding a cell cycle regulatory factor limits rates of cell proliferation. An essential cell cycle transcription factor, E2F1, was found to be post-transcriptionally regulated by TOR and EGFR signaling, and thus served as a candidate growth sensor for this study. Using expression of green fluorescent protein (GFP)-E2F1 transgenes with alterations within the E2f1 5′ untranslated region (UTR), we altered the translation of GFP-E2F1 and changed cell proliferation rates accordingly. Further, we found that 5′UTR upstream open reading frames are TOR-sensitive regulatory components of E2f1 translation. Our observations indicate that growth signaling dependent protein translation is an important regulator of cell proliferation.