The function of MAGED4B (MAGE family member D4B, Ensembl gene identifier ENSG00000187243) is as follows. May enhance ubiquitin ligase activity of RING-type zinc finger-containing E3 ubiquitin-protein ligases. Proposed to act through recruitment and/or stabilization of the Ubl-conjugating enzyme (E2) at the E3:substrate complex. .