Ubiquitin-conjugating Enzyme E2N (UBE2N), also known as Ubiquitin-conjugating Enzyme 13 (Ubc13), forms a functional complex with the catalytically inactive UBE2V2 (human homologue of yeast MMS2) protein.  Human UBE2N/Ubc13 shares 100% and 99% amino acid (aa) sequence identity with the mouse and rat orthologs, respectively, while human UBE2V2 shares 99% aa sequence identity with its mouse and rat orthologs.  The UBE2N/UBE2V2 Complex functions with Ubiquitin ligases (E3s), including RNF111 and RNF8, to synthesize Lys63-linked Ubiquitin chains that can either be unanchored or attached to target proteins.  The UBE2N/UBE2V2 complex has important roles in facilitating responses to various forms of DNA damage.