An intrinsically disordered region controlling condensation of a circadian clock component and rhythmic transcription in the liver

Circadian gene transcription is fundamental to metabolic physiology. Here we report that the nuclear recep-tor REV-ERBa, a repressive component of the molecular clock, forms circadian condensates in the nuclei of mouse liver. These condensates are dictated by an intrinsically disordered region (IDR) located in the pro-tein's hinge region which specifically concentrates nuclear receptor corepressor 1 (NCOR1) at the genome. IDR deletion diminishes the recruitment of NCOR1 and disrupts rhythmic gene transcription in vivo. REV-ERBa condensates are located at high-order transcriptional repressive hubs in the liver genome that are highly correlated with circadian gene repression. Deletion of the IDR disrupts transcriptional repressive hubs and diminishes silencing of target genes by REV-ERBa. This work demonstrates physiological circadian protein condensates containing REV-ERBa whose IDR is required for hub formation and the control of rhyth-mic gene expression.