InterPro domain: IPR005747

This entry represents endonuclease MutS2. MutS2 is a paralogue of MutS and is not involved in DNA mismatch repair but in the suppression of homologous recombination [ 1 , 2 , 3 , 4 ]. It may therefore have a key role in the control of bacterial genetic diversity.

The MutS family of proteins is named after the Salmonella typhimurium MutS protein involved in mismatch repair. Homologues of MutS have been found in many species including eukaryotes (MSH 1, 2, 3, 4, 5, and 6 proteins), archaea and bacteria, and together these proteins have been grouped into the MutS family. Although many of these proteins have similar activities to the E. coli MutS, there is significant diversity of function among the MutS family members. Inter-species homologues may have arisen through frequent ancient horizontal gene transfer of MutS (and MutL) from bacteria to archaea and eukaryotes via endosymbiotic ancestors of mitochondria and chloroplasts [ 5 ].

1. Suppression of homologous and homeologous recombination by the bacterial MutS2 protein. Mol. Cell 17, 113-20
2. Structural and functional divergence of MutS2 from bacterial MutS1 and eukaryotic MSH4-MSH5 homologs. J. Bacteriol. 187, 3528-37
3. Crystal structure of MutS2 endonuclease domain and the mechanism of homologous recombination suppression. J. Biol. Chem. 283, 33417-27
4. Thermus thermophilus MutS2, a MutS paralogue, possesses an endonuclease activity promoted by MutL. J. Biochem. 135, 375-84
5. The origins and early evolution of DNA mismatch repair genes--multiple horizontal gene transfers and co-evolution. Nucleic Acids Res. 35, 7591-603