title: Phosphorylation of p300 by ATM controls the stability of NBS1.
abstract: Acetyltransferase, p300 is a transcriptional cofactor of signal-responsive transcriptional regulation. The surveillance kinase ataxia-telangiectasia mutated (ATM) plays a central role in regulation of a wide range of cellular DNA damage responses. Here, we investigated whether and how ATM mediates phosphorylation of p300 in response to DNA damage and how p300 phosphorylation is functionally linked to DNA damage. ATM-phosphorylated p300 in vitro and in vivo, in response to DNA damage. Phosphorylation of p300 proteins was observed upon gamma-irradiation in ATM(+) cells but not ATM(-) cells. Importantly, expression of nonphosphorylatable serine to alanine form of p300 (S106A) destabilized both p300 and NBS1 proteins, after DNA damage. These data demonstrate that ATM transduces a DNA damage signal to p300, and that ATM-dependent phosphorylation of p300 is required for stabilization of NBS1 proteins in response to DNA damage.
authors.affiliation: Department of Molecular Science and Technology, College of Natural Sciences, Ajou University, Suwon 443-749, Republic of Korea.
authors.forename: Eun Ryoung
authors.initials: ER
authors.lastname: Jang
authors.forename: Jae Duk
authors.initials: JD
authors.lastname: Choi
authors.forename: Gajin
authors.initials: G
authors.lastname: Jeong
authors.forename: Jong-Soo
authors.initials: JS
authors.lastname: Lee
mesh_terms: D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins / Q000378:metabolism*; D004249:DNA Damage; D004268:DNA-Binding Proteins / Q000378:metabolism*; D050881:E1A-Associated p300 Protein / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D055550:Protein Stability; D012694:Serine / Q000235:genetics / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C112156:NBN protein, human; D009687:Nuclear Proteins; D025521:Tumor Suppressor Proteins; D012694:Serine; D050881:E1A-Associated p300 Protein; C494360:EP300 protein, human; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases