EMD-33043
CryoEM structure of dsDNA-RuvB-RuvA domain3 complex
EMD-33043
Single-particle7.02 Å
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Map released: 15/03/2023
Last modified: 20/09/2023
Sample Organism:
synthetic construct,
Pseudomonas aeruginosa PAO1
Sample: RuvB region of the RuvA-RuvB-Holliday junction complex
Fitted models: 7x7p (Avg. Q-score: 0.186)
Deposition Authors: Lin Z
,
Qu Q
,
Zhang X
,
Zhou Z
Sample: RuvB region of the RuvA-RuvB-Holliday junction complex
Fitted models: 7x7p (Avg. Q-score: 0.186)
Deposition Authors: Lin Z
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Cryo-EM structure of the RuvAB-Holliday junction intermediate complex from Pseudomonas aeruginosa.
Zhang X
,
Zhou Z
,
Dai L,
Chao Y,
Liu Z
,
Huang M,
Qu Q
,
Lin Z
(2023) Front Plant Sci , 14 , 1139106 - 1139106
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(2023) Front Plant Sci , 14 , 1139106 - 1139106
Abstract:
Holliday junction (HJ) is a four-way structured DNA intermediate in homologous recombination. In bacteria, the HJ-specific binding protein RuvA and the motor protein RuvB together form the RuvAB complex to catalyze HJ branch migration. Pseudomonas aeruginosa (P. aeruginosa, Pa) is a ubiquitous opportunistic bacterial pathogen that can cause serious infection in a variety of host species, including vertebrate animals, insects and plants. Here, we describe the cryo-Electron Microscopy (cryo-EM) structure of the RuvAB-HJ intermediate complex from P. aeruginosa. The structure shows that two RuvA tetramers sandwich HJ at the junction center and disrupt base pairs at the branch points of RuvB-free HJ arms. Eight RuvB subunits are recruited by the RuvA octameric core and form two open-rings to encircle two opposite HJ arms. Each RuvB subunit individually binds a RuvA domain III. The four RuvB subunits within the ring display distinct subdomain conformations, and two of them engage the central DNA duplex at both strands with their C-terminal β-hairpins. Together with the biochemical analyses, our structure implicates a potential mechanism of RuvB motor assembly onto HJ DNA.
Holliday junction (HJ) is a four-way structured DNA intermediate in homologous recombination. In bacteria, the HJ-specific binding protein RuvA and the motor protein RuvB together form the RuvAB complex to catalyze HJ branch migration. Pseudomonas aeruginosa (P. aeruginosa, Pa) is a ubiquitous opportunistic bacterial pathogen that can cause serious infection in a variety of host species, including vertebrate animals, insects and plants. Here, we describe the cryo-Electron Microscopy (cryo-EM) structure of the RuvAB-HJ intermediate complex from P. aeruginosa. The structure shows that two RuvA tetramers sandwich HJ at the junction center and disrupt base pairs at the branch points of RuvB-free HJ arms. Eight RuvB subunits are recruited by the RuvA octameric core and form two open-rings to encircle two opposite HJ arms. Each RuvB subunit individually binds a RuvA domain III. The four RuvB subunits within the ring display distinct subdomain conformations, and two of them engage the central DNA duplex at both strands with their C-terminal β-hairpins. Together with the biochemical analyses, our structure implicates a potential mechanism of RuvB motor assembly onto HJ DNA.