Coupling of human DNA excision repair and the DNA damage checkpoint in a defined in vitro system.


Journal Article

DNA repair and DNA damage checkpoints work in concert to help maintain genomic integrity. In vivo data suggest that these two global responses to DNA damage are coupled. It has been proposed that the canonical 30 nucleotide single-stranded DNA gap generated by nucleotide excision repair is the signal that activates the ATR-mediated DNA damage checkpoint response and that the signal is enhanced by gap enlargement by EXO1 (exonuclease 1) 5' to 3' exonuclease activity. Here we have used purified core nucleotide excision repair factors (RPA, XPA, XPC, TFIIH, XPG, and XPF-ERCC1), core DNA damage checkpoint proteins (ATR-ATRIP, TopBP1, RPA), and DNA damaged by a UV-mimetic agent to analyze the basic steps of DNA damage checkpoint response in a biochemically defined system. We find that checkpoint signaling as measured by phosphorylation of target proteins by the ATR kinase requires enlargement of the excision gap generated by the excision repair system by the 5' to 3' exonuclease activity of EXO1. We conclude that, in addition to damaged DNA, RPA, XPA, XPC, TFIIH, XPG, XPF-ERCC1, ATR-ATRIP, TopBP1, and EXO1 constitute the minimum essential set of factors for ATR-mediated DNA damage checkpoint response.

Full Text

Duke Authors

Cited Authors

  • Lindsey-Boltz, LA; Kemp, MG; Reardon, JT; DeRocco, V; Iyer, RR; Modrich, P; Sancar, A

Published Date

  • February 21, 2014

Published In

Volume / Issue

  • 289 / 8

Start / End Page

  • 5074 - 5082

PubMed ID

  • 24403078

Pubmed Central ID

  • 24403078

Electronic International Standard Serial Number (EISSN)

  • 1083-351X

Digital Object Identifier (DOI)

  • 10.1074/jbc.M113.542787


  • eng

Conference Location

  • United States