The histone chaperone FACT facilitates heterochromatin spreading by regulating histone turnover and H3K9 methylation states.

ABSTRACT: Heterochromatin formation requires three distinct steps: nucleation, self-propagation (spreading) along the chromosome, and faithful maintenance after each replication cycle. Impeding any of those steps induces heterochromatin defects and improper gene expression. The essential histone chaperone FACT (facilitates chromatin transcription) has been implicated in heterochromatin silencing, but the mechanisms by which FACT engages in this process remain opaque. Here, we pinpoint its function to the heterochromatin spreading process in fission yeast. FACT impairment reduces nucleation-distal H3K9me3 and HP1/Swi6 accumulation at subtelomeres and derepresses genes in the vicinity of heterochromatin boundaries. FACT promotes spreading by repressing heterochromatic histone turnover, which is crucia

SUBMITTER: Murawska M 

PROVIDER: S-EPMC8608617 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature