Jiao and Liu (Research Articles, 16 October 2015, aac4383) reported the crystal structure of the protein complex polycomb repressive complex 2 from Chaetomium thermophilum This landmark structure has brought invaluable insights into the activation mechanism of this essential methyltransferase. However, the analysis of the x-ray data discussed below suggests that the description of oncogenic H3K...

RET finger protein (RFP) belongs to the large B-box RING finger protein family and is known to become oncogenic by fusion with RET tyrosine kinase. Although RFP is reported to be a nuclear protein that is present in the nuclear matrix, its function is largely unknown. Here we show that RFP interacts with Enhancer of Polycomb (EPC) and strongly represses the gene transcription. Yeast two-hybrid ...

Polycomb repressive complex 2 (PRC2) deposits repressive epigenetic marks that silence inappropriate gene expression programs. Recent work from DelgadoOlguín et al1 in conjunction with studies from other laboratories2–4 show that PRC2 activity in cardiac progenitors influences growth and gene expression of mature cardiomyocytes. These studies illustrate the power of epigenetic mechanisms to ret...

Epigenetic silencing of genes in association with aberrant promoter DNA hypermethylation has emerged as a significant mechanism in the development of human cancers. Such genes are also often targets of the polycomb group repressive complexes in embryonic cells. The polycomb repressive complex 2 (PRC2) has been best studied in this regard. We now examine a link between PRC1 and cancer-specific g...

Zhang et al suggested that in the crystal structure of a polycomb repressive complex 2 from Chaetomium thermophilum (ctPRC2), a flexible linker region, but not the H3K27M cancer mutant peptide, better fits the electron density. Based on our new data, we agree with this alternative interpretation and provide the crystal structure of ctPRC2 bound to a bona fide H3K27M sequence.

The Polycomb repressive complex 2 (PRC2) is a conserved chromatin-remodelling that catalyses the trimethylation of histone H3 lysine 27 (H3K27me3), mark associated with gene silencing. PRC2 regulates chromatin structure and expression during organismal tissue development homeostasis in adult. core subunits are various accessory proteins modulate its function recruitment to target genes. multime...

Recruitment of the Polycomb repressive complexes PRC1 and PRC2 by Xist RNA is an important paradigm for chromatin regulation by long noncoding RNAs. Here, we show that the noncanonical Polycomb group RING finger 3/5 (PCGF3/5)-PRC1 complex initiates recruitment of both PRC1 and PRC2 in response to Xist RNA expression. PCGF3/5-PRC1-mediated ubiquitylation of histone H2A signals recruitment of oth...

Polycomb proteins maintain cell identity by repressing the expression of developmental regulators specific for other cell types. Polycomb repressive complex-2 (PRC2) catalyzes trimethylation of histone H3 lysine-27 (H3K27me3). Although repressed, PRC2 targets are generally associated with the transcriptional initiation marker H3K4me3, but the significance of this remains unclear. Here, we ident...

In Arabidopsis thaliana, the promotion of flowering by cold temperatures, vernalization, is regulated via a floral-repressive MADS box transcription factor, FLOWERING LOCUS C (FLC). Vernalization leads to the epigenetic repression of FLC expression, a process that requires the polycomb group (PcG) protein VERNALIZATION 2 (VRN2) and the plant homeodomain protein VERNALIZATION INSENSITIVE 3 (VIN3...