E3 ubiquitin-protein ligase BRE1B; BRE1-B; 95 kD retinoblastoma-associated protein; RBP95; RING finger protein 40 (RNF40, BRE1B, KIAA0661)

Function

• E3 ubiquitin ligase protein
  • ubiquitin conjugation, 3rd step
• monoubiquitination of Lys-120 of histone H2B. H2B
  • specific tag for epigenetic transcriptional activation
  • required for histone H3 Lys-4 & Lys-79 methylation
• forms a ubiquitin ligase complex in cooperation with E2 enzyme UBE2E1
• histone code & gene regulation
• transcriptional activation of Hox genes.
• component of the RNF20/40 complex
• interacts with RB1

Structure

homodimer

Compartment

nucleus

Expression

ubiquitously expressed

More general terms

• E3 ubiquitin ligase
• ring finger protein
• phosphoprotein
• nuclear protein

Component of

• BRE1A/BRE1B/UBE2E1 (RNF20/40) complex

Database

• OMIM: https://mirror.omim.org/entry/607700
• UniProt: http://www.uniprot.org/uniprot/O75150.html