Caffeine Abolishes the Mammalian G2/M DNA Damage Checkpoint by Inhibiting Ataxia-Telangiectasia-mutated Kinase Activity*

  title={Caffeine Abolishes the Mammalian G2/M DNA Damage Checkpoint by Inhibiting Ataxia-Telangiectasia-mutated Kinase Activity*},
  author={Bin-Bing S. Zhou and Priya Chaturvedi and Kevin J. Spring and Shaun P. Scott and Roy A. Johanson and Rubin Mishra and Michael Mattern and James D. Winkler and Kum Kum Khanna},
  journal={The Journal of Biological Chemistry},
  pages={10342 - 10348}
Recent evidence indicates that arrest of mammalian cells at the G2/M checkpoint involves inactivation and translocation of Cdc25C, which is mediated by phosphorylation of Cdc25C on serine 216. Data obtained with a phospho-specific antibody against serine 216 suggest that activation of the DNA damage checkpoint is accompanied by an increase in serine 216 phosphorylated Cdc25C in the nucleus after exposure of cells to γ-radiation. Prior treatment of cells with 2 mm caffeine inhibits such a change… 

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