Mutations in the PCNA DNA Polymerase Clamp of Saccharomyces cerevisiae Reveal Complexities of the Cell Cycle and Ploidy on Heterochromatin Assembly.

ABSTRACT: In Saccharomyces cerevisiae, transcriptional silencing at HML and HMR maintains mating-type identity. The repressive chromatin structure at these loci is replicated every cell cycle and must be re-established quickly to prevent transcription of the genes at these loci. Mutations in a component of the replisome, the proliferating cell nuclear antigen (PCNA), encoded by POL30, cause a loss of transcriptional silencing at HMR We used an assay that captures transient losses of silencing at HML and HMR to perform extended genetic analyses of the pol30-6, pol30-8, and pol30-79 alleles. All three alleles destabilized silencing only transiently and only in cycling cells. Whereas pol30-8 caused loss of silencing by disrupt

SUBMITTER: Brothers M 

PROVIDER: S-EPMC6781887 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature