Expanded roles of the origin recognition complex in the architecture and function of silenced chromatin in Saccharomyces cerevisiae.

摘要: The silenced chromatin at the cryptic mating-type loci (HML and HMR) of Saccharomyces cerevisiae requires a cell cycle event between early S phase G(2)/M to achieve repression. Although DNA replication per se is not essential for silencing, mutations in many proteins involved affect silencing. Each four silencers, which flank loci, includes an origin recognition complex (ORC) binding site (ACS). ORC directly interacted with Sir1 recruits silencers. This study describes additional roles architecture chromatin. Using immunoprecipitation (ChIP) analysis, we found that physically interacts throughout internal regions HMR as well interaction depended on presence Sir and, part, HMR-I silencer. remained associated even when these were recombinationally separated from Moreover, could be recruited silencers lacking ACS through its interaction.