8GYK

CryoEM structure of the RAD51_ADP filament

Summary for 8GYK

• Entry DOI: 10.2210/pdb8gyk/pdb
• EMDB information: 34372 36040
• Descriptor: DNA repair protein RAD51 homolog 1, ADENOSINE-5'-DIPHOSPHATE, MAGNESIUM ION (3 entities in total)
• Functional Keywords: recombinase, atpase, dna repair protein, dna binding, recombination
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 8
• Total formula weight: 299685.05

Authors

Miki, Y.,Luo, S.C.,Ho, M.C. (deposition date: 2022-09-22, release date: 2023-08-30)

Primary citation

Luo, S.C.,Yeh, M.C.,Lien, Y.H.,Yeh, H.Y.,Siao, H.L.,Tu, I.P.,Chi, P.,Ho, M.C.
A RAD51-ADP double filament structure unveils the mechanism of filament dynamics in homologous recombination.
Nat Commun, 14:4993-4993, 2023

PubMed Abstract: ATP-dependent RAD51 recombinases play an essential role in eukaryotic homologous recombination by catalyzing a four-step process: 1) formation of a RAD51 single-filament assembly on ssDNA in the presence of ATP, 2) complementary DNA strand-exchange, 3) ATP hydrolysis transforming the RAD51 filament into an ADP-bound disassembly-competent state, and 4) RAD51 disassembly to provide access for DNA repairing enzymes. Of these steps, filament dynamics between the ATP- and ADP-bound states, and the RAD51 disassembly mechanism, are poorly understood due to the lack of near-atomic-resolution information of the ADP-bound RAD51-DNA filament structure. We report the cryo-EM structure of ADP-bound RAD51-DNA filaments at 3.1 Å resolution, revealing a unique RAD51 double-filament that wraps around ssDNA. Structural analysis, supported by ATP-chase and time-resolved cryo-EM experiments, reveals a collapsing mechanism involving two four-protomer movements along ssDNA for mechanical transition between RAD51 single- and double-filament without RAD51 dissociation. This mechanism enables elastic change of RAD51 filament length during structural transitions between ATP- and ADP-states.

PubMed: 37591853
DOI: 10.1038/s41467-023-40672-5

Experimental method

ELECTRON MICROSCOPY (3.14 Å)