A Giant Ubiquitin-conjugating Enzyme Related to IAP Apoptosis Inhibitors

摘要: Ubiquitin-conjugating enzymes (UBC) catalyze the covalent attachment of ubiquitin to target proteins and are distinguished by presence a UBC domain required for catalysis. Previously identified members this enzyme family small function primarily in selective proteolysis pathways. Here we describe BRUCE (BIR repeat containing ubiquitin-conjugating enzyme), giant (528-kD) from mice. is membrane associated localizes Golgi compartment vesicular system. Remarkably, addition being an active enzyme, bears baculovirus inhibitor apoptosis (BIR) motif, which date has been exclusively found inhibitors IAP-related protein family. The BIR motifs IAP indispensable their anti–cell death activity thought through protein–protein interaction. This suggests that may combine properties IAP-like indicates structurally functionally more diverse than previously expected.