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APOBEC3A can activate the DNA damage response and cause cell-cycle arrest.

ABSTRACT: Human apolipoprotein-B mRNA-editing catalytic polypeptide-like 3 (APOBEC3) proteins constitute a family of cytidine deaminases that mediate restriction of retroviruses, endogenous retro-elements and DNA viruses. It is well established that these enzymes are potent mutators of viral DNA, but it is unclear whether their editing activity is a threat to the integrity of the cellular genome. We show that expression of APOBEC3A can lead to induction of DNA breaks and activation of damage responses in a deaminase-dependent manner. Consistent with these observations, APOBEC3A expression induces cell-cycle arrest. These results indicate that cellular DNA is vulnerable to APOBEC3 activity and deregulated expression of APOBEC3A could threaten genomic integrity.

SUBMITTER: Landry S

PROVIDER: S-EPMC3090015 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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APOBEC3A can activate the DNA damage response and cause cell-cycle arrest.

Landry Sébastien S Narvaiza Iñigo I Linfesty Daniel C DC Weitzman Matthew D MD

EMBO reports 20110401 5

Human apolipoprotein-B mRNA-editing catalytic polypeptide-like 3 (APOBEC3) proteins constitute a family of cytidine deaminases that mediate restriction of retroviruses, endogenous retro-elements and DNA viruses. It is well established that these enzymes are potent mutators of viral DNA, but it is unclear whether their editing activity is a threat to the integrity of the cellular genome. We show that expression of APOBEC3A can lead to induction of DNA breaks and activation of damage responses in ...[more]

PMID: 21460793

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