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ATM-dependent phosphorylation of heterogeneous nuclear ribonucleoprotein K promotes p53 transcriptional activation in response to DNA damage.

ABSTRACT: Previous work has established that heterogeneous nuclear ribonucleoprotein K (hnRNP K) is stabilized in an ATM-dependent manner in response to DNA damage and acts as a cofactor for p53-mediated transcription. Here, we show that in response to DNA damage caused by ionizing radiation, hnRNP K is phosphorylated in an ATM-dependent manner. Furthermore, our data indicate that ATM-dependent hnRNP K phosphorylation is required for its stabilization and its function as a p53 transcriptional cofactor in response to DNA damage. These findings thereby establish hnRNP K as an ATM target and help define how ATM orchestrates p53-dependent transcriptional responses in response to genotoxic stress.

SUBMITTER: Moumen A

PROVIDER: S-EPMC3594270 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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ATM-dependent phosphorylation of heterogeneous nuclear ribonucleoprotein K promotes p53 transcriptional activation in response to DNA damage.

Moumen Abdeladim A Magill Christine C Dry Katherine L KL Jackson Stephen P SP

Cell cycle (Georgetown, Tex.) 20130123 4

Previous work has established that heterogeneous nuclear ribonucleoprotein K (hnRNP K) is stabilized in an ATM-dependent manner in response to DNA damage and acts as a cofactor for p53-mediated transcription. Here, we show that in response to DNA damage caused by ionizing radiation, hnRNP K is phosphorylated in an ATM-dependent manner. Furthermore, our data indicate that ATM-dependent hnRNP K phosphorylation is required for its stabilization and its function as a p53 transcriptional cofactor in ...[more]

PMID: 23343766

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