Bimodal distribution of Tet1 on bivalent genes. (A) Heatmaps of H3K4me3, H3K27me3, 5hmC, Ezh2, Suz12, Tet1-C , Tet1-N , Tet1-Wu , Sin3a #1 (Abcam), and Sin3a #2 (Santa Cruz Biotechnology) on the transcription start site (TSS) of genes rank-ordered by their H3K27me3 level. (B) Distribution frequency of Tet1 binding obtained by clustering of Tet1 binding data by k-means algorithm revealed two different Tet1 occupancy profiles on gene promoters.(C) Tet1, Sin3a and Suz12 occupancy around the TSS (± 2 kb) of H3K27me3-negative (upper panel) or H3K27me3-positive (lower panel) genes. (D) Fitting of the Tet1 binding in H3K27me3-positive genes revealed two Gaussian profiles, one centered -39 bp upstream from the TSS, and the other centered +455 bp downstream from the TSS.