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-Structure paper
Title | Identification of fidelity-governing factors in human recombinases DMC1 and RAD51 from cryo-EM structures. |
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Journal, issue, pages | Nat Commun, Vol. 12, Issue 1, Page 115, Year 2021 |
Publish date | Jan 14, 2021 |
Authors | Shih-Chi Luo / Hsin-Yi Yeh / Wei-Hsuan Lan / Yi-Min Wu / Cheng-Han Yang / Hao-Yen Chang / Guan-Chin Su / Chia-Yi Lee / Wen-Jin Wu / Hung-Wen Li / Meng-Chiao Ho / Peter Chi / Ming-Daw Tsai / |
PubMed Abstract | Both high-fidelity and mismatch-tolerant recombination, catalyzed by RAD51 and DMC1 recombinases, respectively, are indispensable for genomic integrity. Here, we use cryo-EM, MD simulation and ...Both high-fidelity and mismatch-tolerant recombination, catalyzed by RAD51 and DMC1 recombinases, respectively, are indispensable for genomic integrity. Here, we use cryo-EM, MD simulation and functional analysis to elucidate the structural basis for the mismatch tolerance of DMC1. Structural analysis of DMC1 presynaptic and postsynaptic complexes suggested that the lineage-specific Loop 1 Gln244 (Met243 in RAD51) may help stabilize DNA backbone, whereas Loop 2 Pro274 and Gly275 (Val273/Asp274 in RAD51) may provide an open "triplet gate" for mismatch tolerance. In support, DMC1-Q244M displayed marked increase in DNA dynamics, leading to unobservable DNA map. MD simulation showed highly dispersive mismatched DNA ensemble in RAD51 but well-converged DNA in DMC1 and RAD51-V273P/D274G. Replacing Loop 1 or Loop 2 residues in DMC1 with RAD51 counterparts enhanced DMC1 fidelity, while reciprocal mutations in RAD51 attenuated its fidelity. Our results show that three Loop 1/Loop 2 residues jointly enact contrasting fidelities of DNA recombinases. |
External links | Nat Commun / PubMed:33446654 / PubMed Central |
Methods | EM (helical sym.) |
Resolution | 3.2 - 3.47 Å |
Structure data | EMDB-30308, PDB-7c98: EMDB-30309, PDB-7c99: EMDB-30310, PDB-7c9a: EMDB-30311, PDB-7c9c: EMDB-30366, PDB-7cgy: |
Chemicals | ChemComp-CA: ChemComp-ANP: |
Source |
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Keywords | RECOMBINATION/DNA / meiotic homologous recombination / DNA repair / ATPase / RECOMBINATION / RECOMBINATION-DNA complex / meitotic homologous recombination |