Increased respiration in the sch9Delta mutant is required for increasing chronological life span but not replicative life span.

ABSTRACT: Loss of the protein kinase Sch9p increases both the chronological life span (CLS) and the replicative life span (RLS) of Saccharomyces cerevisiae by mimicking calorie restriction, but the physiological consequences of SCH9 deletion are poorly understood. By transcriptional profiling of an sch9Delta mutant, we show that mitochondrial electron transport chain genes are upregulated. Accordingly, protein levels of electron transport chain subunits are increased and the oxygen consumption rate is enhanced in the sch9Delta mutant. Deletion of HAP4 and CYT1, both of which are essential for respiration, revert the sch9Delta mutant respiratory rate back to a lower-than-wild-type level. These alterations of the electron transport chain almost completely blocked CLS extension by the sch9Delta mutatio

SUBMITTER: Lavoie H 

PROVIDER: S-EPMC2446671 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature