RNF20
Function
Component of the RNF20/40 E3 ubiquitin-protein ligase complex that mediates monoubiquitination of 'Lys-120' of histone H2B (H2BK120ub1). H2BK120ub1 gives a specific tag for epigenetic transcriptional activation and is also prerequisite for histone H3 'Lys-4' and 'Lys-79' methylation (H3K4me and H3K79me, respectively). It thereby plays a central role inb histone code and gene regulation. The RNF20/40 complex forms a H2B ubiquitin ligase complex in cooperation with the E2 enzyme UBE2A or UBE2B; reports about the cooperation with UBE2E1/UBCH are contradictory. Required for transcriptional activation of Hox genes. Recruited to the MDM2 promoter, probably by being recruited by p53/TP53, and thereby acts as a transcriptional coactivator. Mediates the polyubiquitination of isoform 2 of PA2G4 in cancer cells leading to its proteasome-mediated degradation.
(Microbial infection) Promotes the human herpesvirus 8 (KSHV) lytic cycle by inducing the expression of lytic viral genes including the latency switch gene RTA/ORF50.
Pathway
Protein modification; protein ubiquitination.
Sequence Similarities
Belongs to the BRE1 family.
Tissue Specificity
Expressed in the normal brain and also in malignant gliomas (at protein level).
Cellular localization
- Nucleus
Alternative names
BRE1A, RNF20, E3 ubiquitin-protein ligase BRE1A, BRE1-A, hBRE1, RING finger protein 20, RING-type E3 ubiquitin transferase BRE1A