Figure 5. PRC1-BCOR Complex Requires Both PRC2 and BCL6 for Stable Association and Repression of Bivalent Promoters.

(A) ChIP re-ChIP in the bivalent promoters of CDKN1B and PRDM1 in OCI-Ly7 cells using the indicated antibodies for the first ChIP (1° ab) and the sequential ChIP (2° ab). As negative control, qPCR was performed using primers for a region in chromosome 6 where no BCOR, EZH2, or BCL6 enrichment was found by ChIP-seq read density in GC B cells.

(B and C) qChIP in CDKN1B promoter of SUDHL6 cells treated with (B) 2 µM EZH2 inhibitor GSK343 or control compound GSK669 for 72 hr, and (C) 25 µM BCL6 inhibitor FX1 or vehicle for 6 hr. NC-PRC1, non-canonical PRC1.

Values are shown as means of triplicates or quadruplicates ± SD. t test, *p < 0.05, **p < 0.01, ***p < 0.001. See also Figure S5.