Fig. 2
Stochastic gene expression of PRCa and active genes. a Comparison of PRCa and active genes reveals that PRCa genes are more variable with lower burst frequency levels than active genes (P < 2.2 × 10−16 by the two-tailed Wilcoxon rank sum test). Gene expression variation is represented by DM values. b Expression profiles of PRCa genes show bimodal patterns. The distribution of a gene with bimodal expression is assumed to be expressed as a mixture of two normal distributions (LE and HE states; upper panel). PRCa genes have mixed cell states (on average 49% in HE and 51% in LE) indicating they are either in active state (i.e., active RNAPII and no PRC marks) or in repressed state (unproductive RNAPII and with PRC marks) consistent with cellular heterogeneity, suggested in Brookes et al.5 Error bars represent s.e.m.
