Rad9 plays an important role in DNA mismatch repair through physical interaction with MLH1

Nucleic Acids Res. 2008 Nov;36(20):6406-17. doi: 10.1093/nar/gkn686. Epub 2008 Oct 8.

Abstract

Rad9 is conserved from yeast to humans and plays roles in DNA repair (homologous recombination repair, and base-pair excision repair) and cell cycle checkpoint controls. It has not previously been reported whether Rad9 is involved in DNA mismatch repair (MMR). In this study, we have demonstrated that both human and mouse Rad9 interacts physically with the MMR protein MLH1. Disruption of the interaction by a single-point mutation in Rad9 leads to significantly reduced MMR activity. This disruption does not affect S/M checkpoint control and the first round of G(2)/M checkpoint control, nor does it alter cell sensitivity to UV light, gamma rays or hydroxyurea. Our data indicate that Rad9 is an important factor in MMR and carries out its MMR function specifically through interaction with MLH1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism*
  • Amino Acid Substitution
  • Animals
  • Cell Cycle Proteins / chemistry
  • Cell Cycle Proteins / metabolism
  • Cell Cycle Proteins / physiology*
  • Cell Line
  • DNA Damage
  • DNA Mismatch Repair*
  • Exonucleases / metabolism
  • Gene Deletion
  • Humans
  • Mice
  • MutL Protein Homolog 1
  • Nuclear Proteins / metabolism*
  • Protein Interaction Domains and Motifs
  • Serine / genetics

Substances

  • Adaptor Proteins, Signal Transducing
  • Cell Cycle Proteins
  • HUS1B protein, human
  • MLH1 protein, human
  • Nuclear Proteins
  • rad9 protein
  • Serine
  • Exonucleases
  • Rad1 protein, human
  • MutL Protein Homolog 1