PBAF/cBAF reorganization on H3.3 chromatin regulates BMAL1 activity in the absence of circadian negative feedback.

ABSTRACT: Circadian rhythms in gene expression are coincident with 24 hr dynamics in the recruitment of the core-clock transcription factor heterodimer CLOCK-BMAL1 to chromatin. In the liver, circadian chromatin is characterized by rhythmic histone modifications and the deposition of histone variant H2A.Z. However, other histone variants and remodelers that work in conjunction with CLOCK-BMAL1 on variant chromatin remain poorly understood. Here, we reveal that H3.3 variant histone deposition peaks during the daytime in liver chromatin and that CLOCK-BMAL1 is recruited to H3.3 nucleosomes. Moreover, H3.3:CLOCK-BMAL1 associates with PBAF and BRG1/cBAF complexes - members of the SWI/SNF remodeler family - only during the active phase of the circadian cycle. In clock-disrupted Per1^-/-; Per2

SUBMITTER: Letkova D 

PROVIDER: S-EPMC12511354 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature