Signalling DNA damage by regulating p53 co-factor activity.

Linda Smith; Nicholas B La Thangue

doi:10.4161/cc.4.1.1397

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PubMed · 15655373

Signalling DNA damage by regulating p53 co-factor activity.

Linda Smith·Nicholas B La Thangue

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Abstract

In response to DNA damage the related phosphatidylinositol-3-OH-kinase-like-kinases ATM and ATR phosphorylate downstream protein targets which facilitate the DNA damage response. A new pathway in which ATM phosphorylates the transcriptional co-factor Strap has been elucidated. Phosphorylation causes the stabilization of nuclear Strap and favours the formation of a stress-responsive co-activator complex. Strap activity enhances p53 acetylation, and augments the response to DNA damage. Most interestingly, in AT cells Strap remains cytoplasmic, and a mutant derivative that cannot be phosphorylated by ATM is similarly localised to the cytoplasm. These results argue that Strap is an important downstream effector in the DNA damage response.

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Acetylation Animals Ataxia Telangiectasia Mutated Proteins Carrier Proteins Cell Cycle Proteins DNA Damage DNA-Binding Proteins Humans Mutation Phosphorylation Protein Serine-Threonine Kinases Signal Transduction Tumor Suppressor Protein p53 Tumor Suppressor Proteins Journal Article

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Linda Smith, Nicholas B La Thangue. 2005-01-17. Signalling DNA damage by regulating p53 co-factor activity.. https://doi.org/10.4161/cc.4.1.1397

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