title: Protein phosphatase 5 is necessary for ATR-mediated DNA repair.
abstract: Several recent studies have shown that protein phosphatase 5 (PP5) participates in cell cycle arrest after DNA damage, but its roles in DNA repair have not yet been fully characterized. We investigated the roles of PP5 in the repair of ultraviolet (UV)- and neocarzinostatin (NCS)-induced DNA damage. The results of comet assays revealed different repair patterns in UV- and NCS-exposed U2OS-PS cells. PP5 is only essential for Rad3-related (ATR)-mediated DNA repair. Furthermore, the phosphorylation of 53BP1 and BRCA1, important mediators of DNA damage repair, and substrates of ATR and ATM decreased in U2OS-PS cells exposed to UV radiation. In contrast, the cell cycle arrest proteins p53, CHK1, and CHK2 were normally phosphorylated in U2OS and U2OS-PS cells exposed to UV radiation or treated with NCS. In view of these results, we suggest that PP5 plays a crucial role in ATR-mediated repair of UV-induced DNA damage.
authors.affiliation: Department of Pharmacology, DNA Repair Research Center, Chosun University School of Medicine, 375 Seosuk-Dong, Gwangju 501-759, Republic of Korea.
authors.forename: Yoonsung
authors.initials: Y
authors.lastname: Kang
authors.forename: Hyang-Min
authors.initials: HM
authors.lastname: Cheong
authors.forename: Jung-Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Peter I
authors.initials: PI
authors.lastname: Song
authors.forename: Kwang-Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Sang-Yong
authors.initials: SY
authors.lastname: Kim
authors.forename: Jae Yeoul
authors.initials: JY
authors.lastname: Jun
authors.forename: Ho Jin
authors.initials: HJ
authors.lastname: You
mesh_terms: D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D004249:DNA Damage; D004260:DNA Repair; D015536:Down-Regulation; D006801:Humans; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases; D010749:Phosphoprotein Phosphatases; C089641:protein phosphatase 5