Fig. 1
From: Small molecule inhibitors reveal allosteric regulation of USP14 via steric blockade
Characterization of USP14 and IU1. a Domain structure of human USP14. USP14 comprises two domains: an N-terminal ubiquitin-like domain (UBL, 1-80) and a C-terminal catalytic domain (CAT, 105-494). b IU1 inhibited the Ub-AMC hydrolysis activity of proteasome-activated USP14: 15 μM IU1 exhibited detectable inhibition of 15 nM USP14 activated by 1 nM proteasome. Ub-AMC ubiquitin-7-amino-4-methylcoumarin, Ptsm-VS proteasome inhibited by ubiquitin-vinyl sulfone (Ub-VS). c Chemical structure of IU1. d The Ub-PA assay suggests that IU1 inhibits USP14 activity by preventing substrate binding: 3 μM USP14CAT was preincubated with DMSO or 5 mM IU1 for 1 h at 25 °C and then mixed with 12 μM Ub-PA for 1 h. All the results were visualized by SDS-PAGE and Coomassie blue staining. Ub-PA ubiquitin-propargylamide
