ATR/ATM-mediated phosphorylation of human Rad17 is required for genotoxic stress responses.

Published

Journal Article

Genotoxic stress triggers the activation of checkpoints that delay cell-cycle progression to allow for DNA repair. Studies in fission yeast implicate members of the Rad family of checkpoint proteins, which includes Rad17, Rad1, Rad9 and Hus1, as key early-response elements during the activation of both the DNA damage and replication checkpoints. Here we demonstrate a direct regulatory linkage between the human Rad17 homologue (hRad17) and the checkpoint kinases, ATM and ATR. Treatment of human cells with genotoxic agents induced ATM/ATR-dependent phosphorylation of hRad17 at Ser 635 and Ser 645. Overexpression of a hRad17 mutant (hRad17AA) bearing Ala substitutions at both phosphorylation sites abrogated the DNA-damage-induced G2 checkpoint, and sensitized human fibroblasts to genotoxic stress. In contrast to wild-type hRad17, the hRad17AA mutant showed no ionizing-radiation-inducible association with hRad1, a component of the hRad1-hRad9-hHus1 checkpoint complex. These findings demonstrate that ATR/ATM-dependent phosphorylation of hRad17 is a critical early event during checkpoint signalling in DNA-damaged cells.

Full Text

Duke Authors

Cited Authors

  • Bao, S; Tibbetts, RS; Brumbaugh, KM; Fang, Y; Richardson, DA; Ali, A; Chen, SM; Abraham, RT; Wang, XF

Published Date

  • June 21, 2001

Published In

Volume / Issue

  • 411 / 6840

Start / End Page

  • 969 - 974

PubMed ID

  • 11418864

Pubmed Central ID

  • 11418864

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/35082110

Language

  • eng

Conference Location

  • England