title: Functional cross-talk among Rad51, Rad54, and replication protein A in heteroduplex DNA joint formation.
abstract: Saccharomyces cerevisiae Rad51, Rad54, and replication protein A (RPA) proteins work in concert to make heteroduplex DNA joints during homologous recombination. With plasmid length DNA substrates, maximal DNA joint formation is observed with amounts of Rad51 substantially below what is needed to saturate the initiating single-stranded DNA template, and, relative to Rad51, Rad54 is needed in only catalytic quantities. RPA is still indispensable for optimal reaction efficiency, but its role in this instance is to sequester free single-stranded DNA, which otherwise inhibits Rad51 and Rad54 functions. We also demonstrate that Rad54 helps overcome various reaction constraints in DNA joint formation. These results thus shed light on the function of Rad54 in the Rad51-mediated homologous DNA pairing reaction and also reveal a novel role of RPA in the presynaptic stage of this reaction.
authors.affiliation: Department of Molecular Medicine/Institute of Biotechnology, University of Texas Health Science Center at San Antonio, 78245-3207, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Van Komen
authors.forename: Galina
authors.initials: G
authors.lastname: Petukhova
authors.forename: Stefan
authors.initials: S
authors.lastname: Sigurdsson
authors.forename: Patrick
authors.initials: P
authors.lastname: Sung
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001667:Binding, Competitive; D001671:Biochemistry / Q000379:methods; D020134:Catalytic Domain; D004265:DNA Helicases; D045643:DNA Repair Enzymes; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D008954:Models, Biological; D009692:Nucleic Acid Heteroduplexes; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D051135:Rad51 Recombinase; D011995:Recombination, Genetic; D051716:Replication Protein A; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013696:Temperature; D013997:Time Factors
chemical_list: D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D009692:Nucleic Acid Heteroduplexes; D051716:Replication Protein A; D029701:Saccharomyces cerevisiae Proteins; C495151:RAD51 protein, S cerevisiae; D051135:Rad51 Recombinase; D000251:Adenosine Triphosphatases; C075468:RAD54 protein, S cerevisiae; D004265:DNA Helicases; D045643:DNA Repair Enzymes