作者: Leslie J. Saucedo , Xinsheng Gao , Dominic A. Chiarelli , Ling Li , Duoija Pan
DOI: 10.1038/NCB996
关键词:
摘要: Insulin signalling is a potent stimulator of cell growth and has been proposed to function, at least in part, through the conserved protein kinase TOR (target rapamycin) [corrected]. Recent studies suggest that tuberous sclerosis complex Tsc1-Tsc2 may couple insulin Tor activity However, regulatory mechanism involved remains unclear, additional components are most probably involved. In screen for novel regulators growth, we identified Rheb (Ras homologue enriched brain), member Ras superfamily GTP-binding proteins. Increased levels Drosophila melanogaster promote alter cycle kinetics multiple tissues. mitotic tissues, overexpression accelerates passage G1-S phase without affecting rates division, whereas endoreplicating increases DNA ploidy. Mutation suspends larval prevents progression from first second instar. Genetic biochemical tests indicate functions pathway downstream upstream TOR. Levels rheb mRNA rapidly induced response starvation, overexpressed can drive starved animals, suggesting role nutritional control growth.