Ubiquitinconjugating Enzyme H10 (UbcH10), also known as Ubiquitinconjugating Enzyme E2C (UBE2C), is a 179 amino acid (aa) member of the yeast Ubc4/5 family of Ubiquitin Conjugating Enzymes (E2) and has a predicted molecular weight of 20 kDa. Human UbcH10/UBE2C shares 96% aa sequence identity with mouse and rat UBE2C. UbcH10/UBE2C is an essential mediator of mitotic destruction events and cell cycle progression. UbcH10/UBE2C recognizes TEK sequences in target proteins such as Cyclins A and B, mediates Lys11linked ubiquitination, and promotes target protein degradation in conjunction with APC/C, a Ubiquitin Ligase (E3). The catalytic activity of UbcH10/UBE2C is regulated by a conserved N-terminal extension, which mediates E2E3 interaction. UbcH10/UBE2C is overexpressed in a variety of human cancers, and alternate splice isoforms may contribute to uncontrolled cell proliferation and tumor progression.