Extended Data Fig. 2: CKM-Mediator regulates canonical PRC1 binding.
a, A Venn diagram showing the overlap between CDK8 peaks and Polycomb domains. Number of peaks and percent overlap are indicated. b, Metaplot analysis of CDK8 enrichment at Polycomb domains (n = 2097) in WT and CKM-Mediator (CKM-MED) KO ESCs. c, Heatmaps showing CDK8 ChIPseq signal at Polycomb domains (n = 2097) in WT and CKM-Mediator KO ESCs, sorted by decreasing RING1B signal. d, A representative Western blot analysis (n = 6) of nuclear extracts from WT and CKM-MED KO ESCs probed with the indicated antibodies. TBP and HDAC1 are used as loading controls. e, Comparison between loss of Hi-C signal (difference between CKM-MED-KO and WT) and loss of cPRC1 (PCGF2) binding (log2 fold change) at Polycomb domains. Polycomb domains were divided into equal bins (261 domains each) based on log2 fold change in cPRC1 binding. f, Comparison between loss of Hi-C signal (difference between CKM-MED-KO and WT) and levels of CDK8 binding in WT cells (log2RPKM). Domains were divided into eight bins based on CDK8 RPKM levels.