Pancreatic progenitors suppress regulators of beta-cell differentiation. (A) genes with selective absence of PcG repression in beta-cells often exhibit H3K27me3 enrichment in ES cells or pancreatic progenitors and have CpG islands. The cluster representation shows H3K27me3 (red) in the 249 genes with selective absence of PcG repression in beta-cells in different stages. In the adjacent column, the presence of CpG islands is indicated in black. (B) As expected, genes with selective absence of PcG repression in beta-cells are frequently bivalent in ES cells. In pancreatic progenitors, bivalency in such genes is similar to other differentiated cell types. (C) Genes with selective absence of PcG repression in beta-cells show H3K27me3 repression in both differentiated cell types of distant lineages as well as in pancreatic progenitors. (D) Pancreatic progenitors do not preferentially show a bivalent H3K27me3+ H3K4me3+ state (yellow) for genes with selective absence of PcG repression in their progeny (i.e., acinar and beta-cells), compared with genes with selective absence of PcG repression in distant lineages. (E) Pancreatic multipotent progenitors exhibit H3K27me3 repression of genes involved in pluripotency and alternate endoderm fates, but also in regulators of their progeny.