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RNF38 encodes a nuclear ubiquitin protein ligase that modifies p53.

ABSTRACT: The RNF38 gene encodes a RING finger protein of unknown function. Here we demonstrate that RNF38 is a functional ubiquitin protein ligase (E3). We show that RNF38 isoform 1 is localized to the nucleus by a bipartite nuclear localization sequence (NLS). We confirm that RNF38 is a binding partner of p53 and demonstrate that RNF38 can ubiquitinate p53 in vitro and in vivo. Finally, we show that overexpression of RNF38 in HEK293T cells results in relocalization of p53 to discrete foci associated with PML nuclear bodies. These results suggest RNF38 is an E3 ubiquitin ligase that may play a role in regulating p53.

SUBMITTER: Sheren JE

PROVIDER: S-EPMC3855391 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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RNF38 encodes a nuclear ubiquitin protein ligase that modifies p53.

Sheren Jamie E JE Kassenbrock C Kenneth CK

Biochemical and biophysical research communications 20130822 4

The RNF38 gene encodes a RING finger protein of unknown function. Here we demonstrate that RNF38 is a functional ubiquitin protein ligase (E3). We show that RNF38 isoform 1 is localized to the nucleus by a bipartite nuclear localization sequence (NLS). We confirm that RNF38 is a binding partner of p53 and demonstrate that RNF38 can ubiquitinate p53 in vitro and in vivo. Finally, we show that overexpression of RNF38 in HEK293T cells results in relocalization of p53 to discrete foci associated wit ...[more]

PMID: 23973461

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