E-WMIT-12 - Chromatin immunoprecipitation of mouse polycomb group (PcG) proteins in embryonic stem cells
Submitted on 9 May 2006, released on 9 May 2006, last updated on 4 June 2014
Polycomb group (PcG) proteins are highly conserved from flies to mammals and many of these factors have essential roles in early embryonic development. PcG proteins comprise two multimeric complexes, the Polycomb Repressive complexes 1 and 2 (PRC1 and 2), which have been shown to repress transcription through epigenetic modification of chromatin structure. To gain insight into the role of Polycomb in early development, we have identified PRC1 and PRC2 target genes in mouse embryonic stem (ES) cells using genome-scale location analysis. We found that PRC2 occupies many genes that encode key regulators of development including those encoding transcription factors and components of signaling pathways. These genes are repressed and contain nucleosomes methylated at lysine 27 on histone H3. The majority of PRC2 bound and methylated target genes are co-occupied by PRC1 indicating that these complexes function at a similar set of genes in ES cells. Lack of PRC1 or PRC2 subunits in ES cells results in derepression of target genes and loss of pluripotency. These results provide insight into how PcG proteins contribute to the maintenance of stem cell identity.
ChIP-chip by array, binding site identification
Polycomb complexes repress developmental regulators in murine embryonic stem cells. Laurie A. Boyer; Kathrin Plath1; Julia Zeitlinger; Tobias Brambrink; Lea A. Medeiros; Tong Ihn Lee; Stuart S. Levine; Marius Wernig; Adriana Tajonar; Mridula K. Ray; George W. Bell; Arie P. Otte; Miguel Vidal; David K. Gifford; Richard A. Young; Rudolf Jaenisch. Nature 411:349-353 (2006)