Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. SUMO-conjugating enzyme UBC9 is a protein that in humans is encoded by the UBE2I gene. The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes, or E1s, ubiquitin-conjugating enzymes, or E2s, and ubiquitin-protein... Mehr