Molecular mechanisms of DNA mismatch repair

Mutat Res. 2001 Jul 12;486(2):71-87. doi: 10.1016/s0921-8777(01)00088-x.


DNA mismatch repair (MMR) safeguards the integrity of the genome. In its role in postreplicative repair, this repair pathway corrects base-base and insertion/deletion (I/D) mismatches that have escaped the proofreading function of replicative polymerases. In its absence, cells assume a mutator phenotype in which the rate of spontaneous mutation is greatly elevated. The discovery that defects in mismatch repair segregate with certain cancer predisposition syndromes highlights its essential role in mutation avoidance. Recently, three-dimensional structures of MutS, a key repair protein that recognizes mismatches, have been determined by X-ray crystallography. This article provides an overview of the structural features of MutS proteins and discusses how the structural data together with biochemical and genetic studies reveal new insights into the molecular mechanisms of mismatch repair.

Publication types

  • Review

MeSH terms

  • Adenosine Triphosphatases*
  • Bacterial Proteins / metabolism
  • Base Pair Mismatch*
  • DNA Repair*
  • DNA-Binding Proteins / metabolism
  • Escherichia coli / genetics
  • Escherichia coli Proteins*
  • Eukaryotic Cells
  • Models, Molecular
  • MutS DNA Mismatch-Binding Protein


  • Bacterial Proteins
  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • Adenosine Triphosphatases
  • MutS DNA Mismatch-Binding Protein
  • MutS protein, E coli