UBE2W: ProductsUbiquitin-conjugating Enzyme E2W (UBE2W), also known as Ubiquitin-conjugating Enzyme 16 (UBC16), is a member of the Ubiquitin-conjugating (E2) enzyme family. It has an E2 catalytic core domain with an active site cysteine residue that is required for the formation of a thioester bond with Ubiquitin. There are two isoforms of UBE2W, isoform 1 and isoform 2, with predicted molecular weights of 18.1 kDa and 19.5 kDa, respectively. UBE2W localizes to the nucleus where it promotes the mono-ubiquitination of BRCA1 and FANCD2, both of which contribute to DNA repair pathways. Mono-ubiquitination of the CHIP Ubiquitin ligase (E3), which has been reported to enhance its E3 ligase activity, is also mediated by UBE2W.