UbcH2

Ubiquitin-conjugating enzyme E2 H (UBE2H), a member of the ubiquitin-conjugating enzyme family, is also known as ubiquitin carrier protein H, ubiquitin-conjugating enzyme E2-20K and ubiquitin-protein ligase H. The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. At the same time, ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes, or E1s, ubiquitin-conjugating enzymes, or E2s, and ubiquitin-protein ligases, or E3s. Furthermore,UBE2H can accept ubiquitin from the E1 complex and catalyze its covalent attachment to other proteins. In vitro,UBE2H can aslo catalyze 'Lys-11'- and 'Lys-48'-linked polyubiquitination, and it is capable, in vitro, to ubiquitinate histone H2A.