Phosphorylation of ubiquitin at Ser65 affects its polymerization, targets, and proteome-wide turnover.

ABSTRACT: Ubiquitylation is an essential post-translational modification that regulates numerous cellular processes, most notably protein degradation. Ubiquitin can itself be phosphorylated at nearly every serine, threonine, and tyrosine residue. However, the effect of this modification on ubiquitin function is largely unknown. Here, we characterized the effects of phosphorylation of yeast ubiquitin at serine 65 in vivo and in vitro. We find this post-translational modification to be regulated under oxidative stress, occurring concomitantly with the restructuring of the ubiquitin landscape into a highly polymeric state. Phosphomimetic mutation of S65 recapitulates the oxidative stress phenotype, causing a dramatic accumulation of ubiquitylated proteins and a proteome-wide reduction of protein turnov

SUBMITTER: Swaney DL 

PROVIDER: S-EPMC4576982 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature