Regulation of MDMX nuclear import and degradation by Chk2 and 14-3-3.
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ABSTRACT:
SUBMITTER: LeBron C
PROVIDER: S-EPMC1422166 | biostudies-literature | 2006 Mar
REPOSITORIES: biostudies-literature
Publications
Regulation of MDMX nuclear import and degradation by Chk2 and 14-3-3.
LeBron Cynthia C Chen Lihong L Gilkes Daniele M DM Chen Jiandong J
The EMBO journal 20060302 6
The MDM2 homolog MDMX is an important regulator of p53 during mouse embryonic development. DNA damage promotes MDMX phosphorylation, nuclear translocation, and degradation by MDM2. Here we show that MDMX copurifies with 14-3-3, and DNA damage stimulates MDMX binding to 14-3-3. Chk2-mediated phosphorylation of MDMX on S367 is important for stimulating 14-3-3 binding, MDMX nuclear import by a cryptic nuclear import signal, and degradation by MDM2. Mutation of MDMX S367 inhibits ubiquitination and ...[more]
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