Format

Send to:

Choose Destination
See comment in PubMed Commons below
Oncogene. 1999 Jul 15;18(28):4047-54.

Mammalian Chk2 is a downstream effector of the ATM-dependent DNA damage checkpoint pathway.

Author information

  • 1Department of Oncology Research, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA.

Abstract

In response to DNA damage and replication blocks, cells activate pathways that arrest the cell cycle and induce the transcription of genes that facilitate repair. In mammals, ATM (ataxia telangiectasia mutated) kinase together with other checkpoint kinases are important components in this response. We have cloned the rat and human homologs of Saccharomyces cerevisiae Rad 53 and Schizosaccharomyces pombe Cds1, called checkpoint kinase 2 (chk2). Complementation studies suggest that Chk2 can partially replace the function of the defective checkpoint kinase in the Cds1 deficient yeast strain. Chk2 was phosphorylated and activated in response to DNA damage in an ATM dependent manner. Its activation in response to replication blocks by hydroxyurea (HU) treatment, however, was independent of ATM. Using mass spectrometry, we found that, similar to Chk1, Chk2 can phosphorylate serine 216 in Cdc25C, a site known to be involved in negative regulation of Cdc25C. These results suggest that Chk2 is a downstream effector of the ATM-dependent DNA damage checkpoint pathway. Activation of Chk2 might not only delay mitotic entry, but also increase the capacity of cultured cells to survive after treatment with gamma-radiation or with the topoisomerase-I inhibitor topotecan.

PMID:
10435585
[PubMed - indexed for MEDLINE]
Free full text

Publication Types, MeSH Terms, Substances, Secondary Source ID, Grant Support

Publication Types

MeSH Terms

Substances

Secondary Source ID

Grant Support

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Nature Publishing Group
    Loading ...
    Write to the Help Desk