Saccharomyces cerevisiae MSH2, a mispaired base recognition protein, also recognizes Holliday junctions in DNA.
Genetic and biochemical studies have suggested that mismatch repair proteins interact with recombination intermediates to prevent recombination, or to limit the extent of formation of heteroduplex DNA during recombination between divergent DNA sequences. To test the idea that mismatch repair proteins regulate recombination by interacting with recombination intermediates, we investigated whether the Saccharomyces cerevisiae MutS homolog MSH2 could interact with Holliday junctions. Both filter-binding and electron-microscopic analysis showed that MSH2 bound to duplex DNA molecules containing Holliday junctions with a higher affinity than to control duplex DNA, single-stranded DNA or a control duplex DNA containing a mispaired base. The MSH2-Holliday junction complexes were also more stable than MSH2-duplex DNA complexes. This observation suggests that MSH2 protein could directly coordinate the interaction between mismatch repair and genetic recombination observed in genetic studies.
Alani
E
E
Section of Genetics and Development, Cornell University, Ithaca, NY 14853-2703, USA.
Lee
S
S
Kane
M F
MF
Griffith
J
J
Kolodner
R D
RD
D001482:Base Composition; D001483:Base Sequence; D001667:Binding, Competitive; D004260:DNA Repair; D004271:DNA, Fungal / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005656:Fungal Proteins; D008854:Microscopy, Electron / Q000379:methods; D008957:Models, Genetic; D008958:Models, Molecular; D008969:Molecular Sequence Data; D051718:MutS Homolog 2 Protein; D009690:Nucleic Acid Conformation; D009692:Nucleic Acid Heteroduplexes; D009841:Oligonucleotides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009692:Nucleic Acid Heteroduplexes; D009841:Oligonucleotides; D029701:Saccharomyces cerevisiae Proteins; C489751:MSH2 protein, S cerevisiae; D051718:MutS Homolog 2 Protein