Fig. 6: Canonical PRC1 exhibits stable chromatin binding and is restricted to a subset of Polycomb sites.
a A box plot of the percentage of RING1B, CBX7 and PCGF2 molecules in the bound state as determined by SPT. Box plots represent measurements from n > 50 movies from 3 experiments each. Indicated p-values were calculated using a two-tailed Student’s t test. Source data are provided as a Source Data file. b A box plot indicating the fraction of RING1B, CBX7 and PCGF2 molecules exhibiting stable binding. Box plots represent measurements from n > 15 movies from at least 2 experiments. Indicated p-values were calculated using a two-tailed Student’s t test. Source data are provided as a Source Data file. c A box plot illustrating the number of PCGF2 (turquoise) and CBX7 (orange) molecules that are estimated to be bound per kilobase of DNA at RING1B peaks from ChIP-seq in ESCs49,79. Read distributions aggregated from n = 3 biological replicates of PCGF2 and CBX7 ChIP-seq were used to segregate bound PCGF2 and CBX7 molecules into density deciles over RING1B peaks. Source data are provided as a Source Data file. d A genomic snapshot illustrating RING1B, PCGF2 and CBX7 ChIP-seq signal at two strong PRC1 peaks sites and four weaker peaks illustrating the more restricted nature of PCGF2 and CBX7 binding. Values shown below the ChIP-seq signal indicate the estimated number RING1B, PCGF2 and CBX7 molecules bound at a single allele for the indicated peak. In a–c, boxes represent the interquartile range (IQR), the middle line corresponds to the median, and whiskers extend to the largest and smallest values no more than 1.5 x IQR from the box. Values outside of this range are not plotted, but are included in all analyses.
