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Terminal association of Rad54 protein with the Rad51-dsDNA filament.

ABSTRACT: Rad54 protein is a Snf2-related dsDNA-specific ATPase essential for homologous recombination mediated by Rad51 protein, the eukaryotic RecA ortholog. Snf2-related enzymes couple ATP hydrolysis with translocation on dsDNA to remodel or dissociate a wide variety of protein-dsDNA complexes. Rad54 and Rad51 interact through species-specific contacts and mutually stimulate their biochemical activities. Specifically, Rad51 bound to dsDNA, the product of homologous recombination after DNA-strand exchange, stimulates the Rad54 ATPase up to 6-fold, leading to the turnover of Rad51 in the product complex. Electron microscopy visualized the Rad51-Rad54 interaction on dsDNA, showing that an oligomeric form of Rad54 associates preferentially with termini of the Rad51-dsDNA filament. Our data support a mechanism of processive dsDNA-Rad51 filament dissociation by the translocating Rad54 protein.

SUBMITTER: Kiianitsa K

PROVIDER: S-EPMC1502528 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature

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Terminal association of Rad54 protein with the Rad51-dsDNA filament.

Kiianitsa Konstantin K Solinger Jachen A JA Heyer Wolf-Dietrich WD

Proceedings of the National Academy of Sciences of the United States of America 20060619 26

Rad54 protein is a Snf2-related dsDNA-specific ATPase essential for homologous recombination mediated by Rad51 protein, the eukaryotic RecA ortholog. Snf2-related enzymes couple ATP hydrolysis with translocation on dsDNA to remodel or dissociate a wide variety of protein-dsDNA complexes. Rad54 and Rad51 interact through species-specific contacts and mutually stimulate their biochemical activities. Specifically, Rad51 bound to dsDNA, the product of homologous recombination after DNA-strand exchan ...[more]

PMID: 16785421

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