A conserved MutS homolog connector domain interface interacts with MutL homologs.
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.
Mendillo
Marc L
ML
Ludwig Institute for Cancer Research, University of California, San Diego School of Medicine, La Jolla, CA 92093-0669, USA.
Hargreaves
Victoria V
VV
Jamison
Jonathan W
JW
Mo
Ashley O
AO
Li
Sheng
S
Putnam
Christopher D
CD
Woods
Virgil L
VL
Kolodner
Richard D
RD
D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D019943:Amino Acid Substitution; D053843:DNA Mismatch Repair; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D037601:Mannose-Binding Lectin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D000070956:MutL Proteins; D051719:MutS DNA Mismatch-Binding Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D054730:Protein Interaction Domains and Motifs; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012997:Solvents
D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D037601:Mannose-Binding Lectin; C074770:MutL protein, E coli; D011993:Recombinant Fusion Proteins; D012997:Solvents; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D000070956:MutL Proteins; D051719:MutS DNA Mismatch-Binding Protein; C497175:MutS protein, E coli