Gly-Ala repeats induce position- and substrate-specific regulation of 26 S proteasome-dependent partial processing.

ABSTRACT: Partial degradation or regulated ubiquitin proteasome-dependent processing by the 26 S proteasome has been demonstrated, but the underlying molecular mechanisms and the prevalence of this phenomenon remain obscure. Here we show that the Gly-Ala repeat (GAr) sequence of EBNA1 affects processing of substrates via the ubiquitin-dependent degradation pathway in a substrate- and position-specific fashion. GAr-mediated increase in stability of proteins targeted for degradation via the 26 S proteasome was associated with a fraction of the substrates being partially processed and the release of the free GAr. The GAr did not cause a problem for the proteolytic activity of the proteasome, and its fusion to the N terminus of p53 resulted in an increase in the rate of degradation of the entire chimera

SUBMITTER: Daskalogianni C 

PROVIDER: S-EPMC2662073 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature