A conserved two-step binding for the UAF1 regulator to the USP12 deubiquitinating enzyme.

ABSTRACT: Regulation of deubiquitinating enzyme (DUB) activity is an essential step for proper function of cellular ubiquitin signals. UAF1 is a WD40 repeat protein, which binds and activates three important DUBs, USP1, USP12 and USP46. Here, we report the crystal structure of the USP12-Ub/UAF1 complex at a resolution of 2.8Å and of UAF1 at 2.3Å. In the complex we find two potential sites for UAF1 binding, analogous to what was seen in a USP46/UAF1 complex. In line with these observed dual binding states, we show here that USP12/UAF1 complex has 1:2 stoichiometry in solution, with a two-step binding at 4nM and 325nM respectively. Mutagenesis studies show that the fingers sub-domain of USP12 interacts with UAF1 to form the high affinity interface. Our activation studies confirm that the high affinity

SUBMITTER: Dharadhar S 

PROVIDER: S-EPMC5131612 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature