The Polycomb system sustains promoters in a deep OFF state by limiting pre-initiation complex formation to counteract transcription.

ABSTRACT: The Polycomb system has fundamental roles in regulating gene expression during mammalian development. However, how it controls transcription to enable gene repression has remained enigmatic. Here, using rapid degron-based depletion coupled with live-cell transcription imaging and single-particle tracking, we show how the Polycomb system controls transcription in single cells. We discover that the Polycomb system is not a constitutive block to transcription but instead sustains a long-lived deep promoter OFF state, which limits the frequency with which the promoter can enter into a transcribing state. We demonstrate that Polycomb sustains this deep promoter OFF state by counteracting the binding of factors that enable early transcription pre-initiation complex formation and show that this i

SUBMITTER: Szczurek AT 

PROVIDER: S-EPMC11469961 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature