Relative structural and functional roles of multiple deubiquitylating proteins associated with mammalian 26S proteasome.

ABSTRACT: We determined composition and relative roles of deubiquitylating proteins associated with the 26S proteasome in mammalian cells. Three deubiquitylating activities were associated with the 26S proteasome: two from constituent subunits, Rpn11/S13 and Uch37, and one from a reversibly associated protein, Usp14. RNA interference (RNAi) of Rpn11/S13 inhibited cell growth, decreased cellular proteasome activity via disrupted 26S proteasome assembly, and inhibited cellular protein degradation. In contrast, RNAi of Uch37 or Usp14 had no detectable effect on cell growth, proteasome structure or proteolytic capacity, but accelerated cellular protein degradation. RNAi of both Uch37 and Usp14 also had no effect on proteasome structure or proteolytic capacity, but inhibited cellular protein degradation.

SUBMITTER: Koulich E 

PROVIDER: S-EPMC2262970 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature