(A) Barplots showing quantitative H3K27me3 ChIP-PCR from ESCs treated for 24h with either DMSO or EPZ (black and grey bars respectively). ChIP was performed in 3 independent Hhex reporter ESC lines (HFHC10.4, HFHC12.3 and HV9.3) and anti IgG ChIP was performed for clone HV9.3 as a negative control. Error bars represent the standard deviations for duplicated PCR reactions. (B) Schematic representation of the segmentation used to stratify the genomic distribution of H3K27me3 signal (left panel) and a barplot showing the fraction of the genome covered in each category (right panel). The genome is categorized into: CGI TSS (black; ± 5 kb), non-CGI TSS (dark grey; ± 5 kb), intragenic (grey) and intergenic (light grey). The percentage of the genome and the number of intervals representing each category are shown. (C) Barplot depicting the distribution of H3K27me3 ChIP-seq signal across each category as a percentage of total mappable reads for three independent datasets. Percentages for each category are tabulated below the plot. (D) Boxplots depicting the normalised read depths per genomic interval for each genomic fraction. The significance of increased/decreased signal was determined using a Wilcoxon rank-sum test and significant values are indicated (0.05>p≥0.01* and p<0.01**). Significant p values indicated*/** are 2.84 × 10–5, 1.45 × 10–14, 3.39 × 10–54, 9.7 × 10–3, 3.88 × 10–8, 1.1 × 10–20, 2.98 × 10–174, 3.72 × 10–4, 4.36 × 10–7 and 1.04 × 10–4 (in order from top-left to bottom-right by row).