ChIP-seq for Polycomb group proteins and H3K27me3 in ESCs and NSCs

ChIP-seq was performed for Ring1b, Ezh2, Cbx2 and H3K27me3 in ESCs and Ring1b and H3K27me3 in NSCs. This was used to define Polycomb-bound regions and to assess their H3.3 enrichment and turnover using time-ChIP. Cells were crosslinked and ChIP performed using the antibodies indicated. The resulting DNA, along with input DNA samples was made into libraries and sequenced on an Illumina HiSeq 2500.