KDM2B links the Polycomb Repressive Complex 1 (PRC1) to recognition of CpG islands.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 23256043.
- Also identified by DOI 10.7554/eLife.00205 and PMC identifier 3524939.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
CpG islands (CGIs) are associated with most mammalian gene promoters. A subset of CGIs act as polycomb response elements (PREs) and are recognized by the polycomb silencing systems to regulate expression of genes involved in early development. How CGIs function mechanistically as nucleation sites for polycomb repressive complexes remains unknown. Here we discover that KDM2B (FBXL10) specifically recognizes non-methylated DNA in CGIs and recruits the polycomb repressive complex 1 (PRC1). This contributes to histone H2A lysine 119 ubiquitylation (H2AK119ub1) and gene repression. Unexpectedly, we also find that CGIs are occupied by low levels of PRC1 throughout the genome, suggesting that the KDM2B-PRC1 complex may sample CGI-associated genes for susceptibility to polycomb-mediated silencing. These observations demonstrate an unexpected and direct link between recognition of CGIs by KDM2B and targeting of the polycomb repressive system. This provides the basis for a new model describing the functionality of CGIs as mammalian PREs.DOI:http://dx.doi.org/10.7554/eLife.00205.001.
Medical subject headings
- F-Box Proteins
- Gene Silencing
- Genome
- Jumonji Domain-Containing Histone Demethylases
- Polycomb-Group Proteins