The protein encoded by ring finger protein 20 shares similarity with BRE1 of S. cerevisiae. Yeast BRE1 is a ubiquitin ligase required for the ubiquitination of histone H2B and the methylation of histone H3. [provided by RefSeq]. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Gene record to access additional publications.

E3 ubiquitin-protein ligase that mediates monoubiquitination of \'Lys-120\' of histone H2B. H2B \'Lys-120\' ubiquitination gives a specific tag for epigenetic transcriptional activation and is also prerequisite for histone H3 \'Lys-4\' and \'Lys-79\' methylation. Forms a ubiquitin ligase complex in cooperation with the E2 enzyme UBE2E1/UBCH6. It thereby plays a central role in histone code and gene regulation. 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