Ubiquitin-conjugating enzyme E2 D3 (UBE2D3)

Accepts ubiquitin in the E1 complex and catalyzes its covalent attachment to other proteins. Acts as an initiator E2, priming the phosphorylated NFKBIA target at positions'Lys-21' or'Lys-22' using a monoubiquitin.

Ubiquitin chain elongation is then performed by CDC34, building ubiquitin chains from the UBE2D3-primed NFKBIA- linked ubiquitin. Acts also as an initiator E2, in conjunction with RNF8, for the priming of PCNA.