7AI5

MutS in Scanning state

7AI5 の概要

• エントリーDOI: 10.2210/pdb7ai5/pdb
• EMDBエントリー: 11791
• 分子名称: DNA mismatch repair protein MutS, DNA (5'-D(P*CP*TP*AP*TP*AP*GP*GP*GP*CP*GP*AP*AP*TP*TP*GP*GP*GP*TP*AP*CP*CP*G)-3'), DNA (5'-D(P*CP*GP*GP*TP*AP*CP*CP*CP*AP*AP*TP*TP*CP*GP*CP*CP*CP*TP*AP*TP*AP*G)-3'), ... (4 entities in total)
• 機能のキーワード: dna mismatch repair muts, dna binding protein
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 205314.89

構造登録者

Fernandez-Leiro, R.,Bhairosing-Kok, D.,Sixma, T.K.,Lamers, M.H. (登録日: 2020-09-26, 公開日: 2021-03-31, 最終更新日: 2024-05-01)

主引用文献

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

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: 33820992
DOI: 10.1038/s41594-021-00577-7

実験手法

ELECTRON MICROSCOPY (4.4 Å)