BMI1
This gene encodes a ring finger protein that is major component of the polycomb group complex 1 (PRC1). This complex functions through chromatin remodeling as an essential epigenetic repressor of multiple regulatory genes involved in embryonic development and self-renewal in somatic stem cells. This protein also plays a central role in DNA damage repair. This gene is an oncogene and aberrant expression is associated with numerous cancers and is associated with resistance to certain chemotherapies. A pseudogene of this gene is found on chromosome X. Read-through transcription also exists between this gene and the upstream COMM domain containing 3 (COMMD3) gene. [provided by RefSeq, Sep 2015]
Function
Component of a Polycomb group (PcG) multiprotein PRC1-like complex, a complex class required to maintain the transcriptionally repressive state of many genes, including Hox genes, throughout development. PcG PRC1 complex acts via chromatin remodeling and modification of histones; it mediates monoubiquitination of histone H2A 'Lys-119', rendering chromatin heritably changed in its expressibility (PubMed:15386022, PubMed:16359901, PubMed:26151332, PubMed:16714294, PubMed:21772249, PubMed:25355358, PubMed:27827373).
The complex composed of RNF2, UB2D3 and BMI1 binds nucleosomes, and has activity only with nucleosomal histone H2A (PubMed:21772249, PubMed:25355358).
In the PRC1-like complex, regulates the E3 ubiquitin-protein ligase activity of RNF2/RING2 (PubMed:15386022, PubMed:26151332, PubMed:21772249).
Biological Process
Chromatin silencing Source: GO_Central
Hemopoiesis Source: UniProtKB
Histone H2A-K119 monoubiquitination Source: UniProtKB
Negative regulation of G0 to G1 transition Source: Reactome
Negative regulation of gene expression, epigenetic Source: UniProtKB
Negative regulation of transcription by RNA polymerase II Source: UniProtKB
Positive regulation of fibroblast proliferation Source: BHF-UCL
Positive regulation of ubiquitin-protein transferase activity Source: UniProtKB
Regulation of gene expression Source: BHF-UCL
Segment specification Source: ProtInc