conserved MutS homolog connector domain interface interacts with MutL homologs

• Published in: Proceedings of the National Academy of Sciences - PNAS 2009-12, Vol.106 (52), p.22223-22228
• Main Authors: Mendillo, Marc L, Hargreaves, Victoria V, Jamison, Jonathan W, Mo, Ashley O, Li, Sheng, Putnam, Christopher D, Woods, Virgil L. Jr, Kolodner, Richard D
• Format: Article
• Language: English
• Subjects: Adenosine triphosphatase; Adenosine Triphosphatases - chemistry; Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Adenosine Triphosphate - metabolism; Alleles; Amino Acid Substitution; Amino acids; ATP; Binding sites; Biological Sciences; Biosensing techniques; Data processing; DNA; DNA Mismatch Repair; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; DNA, Bacterial - metabolism; E coli; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - chemistry; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Eukaryotes; Genetic mutation; Hydrogen; Mannose-Binding Lectin - chemistry; Mannose-Binding Lectin - genetics; Mannose-Binding Lectin - metabolism; Mass spectrometry; Mass spectroscopy; mismatch repair; Models, Molecular; MSH2 protein; Mutagenesis, Site-Directed; MutL Proteins; MutS DNA Mismatch-Binding Protein - chemistry; MutS DNA Mismatch-Binding Protein - genetics; MutS DNA Mismatch-Binding Protein - metabolism; Protein Conformation; Protein Interaction Domains and Motifs; Proteins; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Saccharomyces cerevisiae; Solvents
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0912250106

Escherichia coli MutS forms a mispair-dependent ternary complex with MutL that is essential for initiating mismatch repair (MMR) but is structurally uncharacterized, in part owing to its dynamic nature. Here, we used hydrogen/deuterium exchange mass spectrometry and other methods to identify a region in the connector domain (domain II) of MutS that binds MutL and is required for mispair-dependent ternary complex formation and MMR. A structurally conserved region in Msh2, the eukaryotic homolog, was required for formation of a mispair-dependent Msh2-Msh6-Mlh1-Pms1 ternary complex. These data indicate that the connector domain of MutS and Msh2 contains the interface for binding MutL and Mlh1-Pms1, respectively, and support a mechanism whereby mispair and ATP binding induces a conformational change that allows the MutS and Msh2 interfaces to interact with their partners.