Activation of the ATM kinase by ionizing radiation and phosphorylation of p53.
Journal Article (Journal Article)
The p53 tumor suppressor protein is activated and phosphorylated on serine-15 in response to various DNA damaging agents. The gene product mutated in ataxia telangiectasia, ATM, acts upstream of p53 in a signal transduction pathway initiated by ionizing radiation. Immunoprecipitated ATM had intrinsic protein kinase activity and phosphorylated p53 on serine-15 in a manganese-dependent manner. Ionizing radiation, but not ultraviolet radiation, rapidly enhanced this p53-directed kinase activity of endogenous ATM. These observations, along with the fact that phosphorylation of p53 on serine-15 in response to ionizing radiation is reduced in ataxia telangiectasia cells, suggest that ATM is a protein kinase that phosphorylates p53 in vivo.
- Canman, CE; Lim, DS; Cimprich, KA; Taya, Y; Tamai, K; Sakaguchi, K; Appella, E; Kastan, MB; Siliciano, JD
- September 11, 1998
Volume / Issue
- 281 / 5383
Start / End Page
- 1677 - 1679
International Standard Serial Number (ISSN)
Digital Object Identifier (DOI)
- United States