UBE2R2: ProductsUbiquitin-conjugating Enzyme E2R 2 (UBE2R2), also known as CDC34B and UBC3B, is a 238 amino acid (aa) member of the Ubiquitin-conjugating (E2) enzyme family with a predicted molecular weight of 27 kDa. Human UBE2R2 shares 100% aa sequence identity with its mouse ortholog and 78% aa sequence identity with its paralog, UBCH3. UBE2R2 has an E2 catalytic core domain with an active site cysteine residue that is required for the formation of a thioester bond with Ubiquitin. The UBE1 Ubiquitin-activating (E1) enzyme, but not the UBA6 E1 enzyme, is capable of charging UBE2R2 with Ubiquitin. UBE2R2 can be phosphorylated on Ser233 by Casein Kinase 2, which promotes an interaction with the beta-TrCP Ubiquitin ligase (E3) and the subsequent ubiquitination and degradation of beta-Catenin.