7AI6
MutS in mismatch bound state
Summary for 7AI6
Entry DOI | 10.2210/pdb7ai6/pdb |
EMDB information | 11791 11792 |
Descriptor | DNA mismatch repair protein MutS, DNA (25-MER), ADENOSINE-5'-DIPHOSPHATE, ... (4 entities in total) |
Functional Keywords | dna mismatch repair muts, dna binding protein |
Biological source | Escherichia coli (strain K12) More |
Total number of polymer chains | 4 |
Total formula weight | 206341.36 |
Authors | Fernandez-Leiro, R.,Bhairosing-Kok, D.,Sixma, T.K.,Lamers, M.H. (deposition date: 2020-09-26, release date: 2021-03-31, Last modification date: 2024-05-01) |
Primary citation | Fernandez-Leiro, R.,Bhairosing-Kok, D.,Kunetsky, V.,Laffeber, C.,Winterwerp, H.H.,Groothuizen, F.,Fish, A.,Lebbink, J.H.G.,Friedhoff, P.,Sixma, T.K.,Lamers, M.H. The selection process of licensing a DNA mismatch for repair. Nat.Struct.Mol.Biol., 28:373-381, 2021 Cited by PubMed Abstract: DNA mismatch repair detects and removes mismatches from DNA by a conserved mechanism, reducing the error rate of DNA replication by 100- to 1,000-fold. In this process, MutS homologs scan DNA, recognize mismatches and initiate repair. How the MutS homologs selectively license repair of a mismatch among millions of matched base pairs is not understood. Here we present four cryo-EM structures of Escherichia coli MutS that provide snapshots, from scanning homoduplex DNA to mismatch binding and MutL activation via an intermediate state. During scanning, the homoduplex DNA forms a steric block that prevents MutS from transitioning into the MutL-bound clamp state, which can only be overcome through kinking of the DNA at a mismatch. Structural asymmetry in all four structures indicates a division of labor between the two MutS monomers. Together, these structures reveal how a small conformational change from the homoduplex- to heteroduplex-bound MutS acts as a licensing step that triggers a dramatic conformational change that enables MutL binding and initiation of the repair cascade. PubMed: 33820992DOI: 10.1038/s41594-021-00577-7 PDB entries with the same primary citation |
Experimental method | ELECTRON MICROSCOPY (6.9 Å) |
Structure validation
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