Context dependent function of the transcriptional regulator Rap1 in gene silencing and activation in Saccharomyces cerevisiae.

ABSTRACT: In Saccharomyces cerevisiae, heterochromatin is formed through interactions between site-specific DNA-binding factors, including the transcriptional activator Rap1, and Sir proteins. Despite a vast understanding of the establishment and maintenance of Sir-silenced chromatin, the mechanism of gene silencing by Sir proteins has remained a mystery. Utilizing high resolution chromatin immunoprecipitation, we found that Rap1, the native activator of the bi-directional HML α promoter, bound its recognition sequence in silenced chromatin and its binding was enhanced by the presence of Sir proteins. In contrast to prior results, various components of transcription machinery were not able to access HML α in the silenced state. These findings disproved the long-standing model of

SUBMITTER: Bondra ER 

PROVIDER: S-EPMC10197613 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature