This Article Full Text Full Text (PDF) Suppl Tables 2-3 A correction has been published Services Download to citation manager PubMed PubMed Citation

Pathways Change in Expression During Replicative Aging in Saccharomyces cerevisiae

Departments of ¹ Biology and ² Mathematics, Pomona College, Claremont, California.

Address correspondence to Laura L. Mays Hoopes, PhD, Biology Department, Pomona College, 609 N. College Ave., Claremont, CA 91711. E-mail: lhoopes{at}pomona.edu

Yeast replicative aging is a process resembling replicative aging in mammalian cells. During aging, wild-type haploid yeast cells enlarge, become sterile, and undergo nucleolar enlargement and fragmentation; we sought gene expression changes during the time of these phenotypic changes. Gene expression studied via microarrays and quantitative real-time reverse-transcription polymerase chain reaction (qPCR) has shown reproducible, statistically significant changes in messenger RNA (mRNA) of genes at 12 and 18–20 generations. Our findings support previously described changes towards aerobic metabolism, decreased ribosome gene expression, and a partial environmental stress response. Our findings include a pseudostationary phase, downregulation of methylation-related metabolism, increased nucleotide excision repair–related mRNA, and a strong upregulation of many of the regulatory subunits of protein phosphatase I (Glc7). These findings are correlated with aging changes in higher organisms as well as with the known involvement of protein phosphorylation states during yeast aging.

Key Words: Replicative aging • Saccharomyces cerevisiae • Gene expression