Fig. 6
From: PRC2 represses transcribed genes on the imprinted inactive X chromosome in mice
A model for PRC2 function in repressing genes. Two classes of X-linked genes are distinguished by chromatin architecture. One gene set is characterized by little to no expression from the paternal-X in WT cells and harbors only H3K27me3 at the TSSs. Upon loss of EED, these genes maintain a relatively closed chromatin conformation and are not predisposed to activation. A second class of genes is characterized in WT cells by RNA PolII occupancy and open chromatin architecture and low-level transcription. Upon loss of EED and H3K27me3, the open chromatin architecture and RNA PolII occupancy facilitate rapid upregulation of these genes