Regulation of p53 localization and activity by Ubc13.

ABSTRACT: The abundance and activity of p53 are regulated largely by ubiquitin ligases. Here we demonstrate a previously undisclosed regulation of p53 localization and activity by Ubc13, an E2 ubiquitin-conjugating enzyme. While increasing p53 stability, Ubc13 decreases p53 transcriptional activity and increases its localization to the cytoplasm, changes that require its ubiquitin-conjugating activity. Ubc13 elicits K63-dependent ubiquitination of p53, which attenuates Hdm2-induced polyubiquitination of p53. Ubc13 association with p53 requires an intact C-terminal domain of p53 and is markedly stronger with a p53 mutant that cannot tetramerize. Expression of Ubc13 in vivo increases the pool of monomeric p53, indicating that Ubc13 affects tetramerization of p53. Significantly, wild-type but not mutan

SUBMITTER: Laine A 

PROVIDER: S-EPMC1636826 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature