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Reconstitution of a human ATR-mediated checkpoint response to damaged DNA.

ABSTRACT: The DNA damage checkpoint response delays cell cycle progression upon DNA damage and prevents genomic instability. Genetic analysis has identified sensor, mediator, signal transducer, and effector components of this global signal transduction pathway. Here we describe an in vitro system with purified human checkpoint proteins that recapitulates key elements of the DNA damage checkpoint. We show that the damage sensor ATR in the presence of topoisomerase II binding protein 1 (TopBP1) mediator/adaptor protein phosphorylates the Chk1 signal-transducing kinase in a reaction that is strongly dependent on the presence of DNA containing bulky base lesions. The dependence on damaged DNA requires DNA binding by TopBP1, and, indeed, TopBP1 shows preferential binding to damaged DNA. This in vitro system provides a useful platform for mechanistic studies of the human DNA damage checkpoint response.

SUBMITTER: Choi JH

PROVIDER: S-EPMC1941640 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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Reconstitution of a human ATR-mediated checkpoint response to damaged DNA.

Choi Jun-Hyuk JH Lindsey-Boltz Laura A LA Sancar Aziz A

Proceedings of the National Academy of Sciences of the United States of America 20070808 33

The DNA damage checkpoint response delays cell cycle progression upon DNA damage and prevents genomic instability. Genetic analysis has identified sensor, mediator, signal transducer, and effector components of this global signal transduction pathway. Here we describe an in vitro system with purified human checkpoint proteins that recapitulates key elements of the DNA damage checkpoint. We show that the damage sensor ATR in the presence of topoisomerase II binding protein 1 (TopBP1) mediator/ada ...[more]

PMID: 17686975

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