IU-1

IU-1 (USP14 inhibitor IU1) is a specific, small molecule inhibitor of deubiquitinating enzyme USP14 with IC50 of 4-5 uM; displays no activity against other human eight DUBs (Uch37, Uch-L1/L3, USP7, etc.); enhances proteasomal degradation in vivo, attenuates cerebral ischemia/reperfusion-induced neuronal injury in mice; also inhibits Dengue virus replication.(In Vitro):Usp14, a proteasome-associated deubiquitinating enzyme, can inhibit the degradation of ubiquitin-protein conjugates, in vivo and in vitro. IU1inhibits the catalytic activity of proteasome associated Usp14 in vitro. The IC50 of IU1 for Usp14 is 4-5 μM. IU1 binds specifically to the activated form of Usp14. IU1 can potentially inhibit Usp14 by preventing its docking on the proteasome, but direct tests of this scenario proved negative. Usp14 inhibition is rapidly established upon addition of IU1 and rapidly reversed upon its removal. IU1 also promotes degradation of Sic1, a CDK inhibitor from S. cerevisiae.