Regulation of longevity and stress resistance by Sch9 in yeast

The protein kinase Akt/protein kinase B (PKB) is implicated in insulin signaling in mammals and functions in a pathway that regulates Longevity and stress resistance in Caenorhabditis elegans. We screened for Long-Lived mutants in nondividing yeast Saccharomyces cerevisiae and identified mutations in adenylate cyclase and SCH9, which is homologous to Akt/PKB, that increase resistance to oxidants and extend Life-span by up to threefold. Stress-resistance transcription factors Msn2/Msn4 and protein kinase Rim15 were required for this life-span extension. These results indicate that Longevity is associated with increased investment in maintenance and show that highly conserved genes play similar roles in Life-span regulation in S. cerevisiae and higher eukaryotes.