Accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins (PubMed:17588522, PubMed:20061386, PubMed:8132613). E2 ubiquitin conjugating enzyme that transfers ubiquitin to MAEA, a core component of the CTLH E3 ubiquitin-protein ligase complex (PubMed:29911972). In vitro catalyzes ‘Lys-11’- and ‘Lys-48’-linked polyubiquitination (PubMed:20061386). Capable, in vitro, to ubiquitinate histone H2A (PubMed:8132613).
