title: A new Schizosaccharomyces pombe chronological lifespan assay reveals that caloric restriction promotes efficient cell cycle exit and extends longevity.
abstract: We describe a new chronological lifespan (CLS) assay for the yeast Schizosaccharomyces pombe. Yeast CLS assays monitor the loss of cell viability in a culture over time, and this new assay shows a continuous decline in viability without detectable regrowth until all cells in the culture are dead. Thus, the survival curve is not altered by the generation of mutants that can grow during the experiments, and one can monitor the entire lifespan of a strain until the number of viable cells has decreased over 10(6)-fold. This CLS assay recapitulates the evolutionarily conserved features of lifespan shortening by over nutrition, lifespan extension by caloric restriction, increased stress resistance of calorically restricted cells and lifespan control by the AKT kinases. Both S. pombe AKT kinase orthologs regulate CLS: loss of sck1(+) extended lifespan in over nutrition conditions, loss of sck2(+) extended lifespan under both normal and over nutrition conditions, and loss of both genes showed that sck1(+) and sck2(+) control different longevity pathways. The longest-lived S. pombe cells showed the most efficient cell cycle exit, demonstrating that caloric restriction links these two processes. This new S. pombe CLS assay will provide a valuable tool for aging research.
authors.affiliation: Department of Molecular Genetics, Cleveland Clinic Lerner College of Medicine at CWRU, 9500 Euclid Avenue NE 20, Cleveland, OH 44195, USA.
authors.forename: Bo-Ruei
authors.initials: BR
authors.lastname: Chen
authors.forename: Kurt W
authors.initials: KW
authors.lastname: Runge
mesh_terms: D000375:Aging / Q000235:genetics / Q000502:physiology*; D031204:Caloric Restriction; D002453:Cell Cycle; D002470:Cell Survival; D015966:Gene Expression Regulation, Fungal / Q000235:genetics / Q000502:physiology; D006801:Humans; D008136:Longevity / Q000235:genetics / Q000502:physiology*; D017382:Reactive Oxygen Species; D012568:Schizosaccharomyces / Q000235:genetics / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics
chemical_list: D017382:Reactive Oxygen Species; D029702:Schizosaccharomyces pombe Proteins