title: In vivo roles of Rad52, Rad54, and Rad55 proteins in Rad51-mediated recombination.
abstract: Repairing a double-strand break by homologous recombination requires binding of the strand exchange protein Rad51p to ssDNA, followed by synapsis with a homologous donor. Here we used chromatin immunoprecipitation to monitor the in vivo association of Saccharomyces cerevisiae Rad51p with both the cleaved MATa locus and the HML alpha donor. Localization of Rad51p to MAT precedes its association with HML, providing evidence of the time needed for the Rad51 filament to search the genome for a homologous sequence. Rad51p binding to ssDNA requires Rad52p. The absence of Rad55p delays Rad51p binding to ssDNA and prevents strand invasion and localization of Rad51p to HML alpha. Lack of Rad54p does not significantly impair Rad51p recruitment to MAT or its initial association with HML alpha; however, Rad54p is required at or before the initiation of DNA synthesis after synapsis has occurred at the 3' end of the invading strand.
authors.affiliation: Rosenstiel Center and Department of Biology, Brandeis University, Waltham, MA 02454, USA.
authors.forename: Neal
authors.initials: N
authors.lastname: Sugawara
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.forename: James E
authors.initials: JE
authors.lastname: Haber
mesh_terms: D002478:Cells, Cultured; D023902:Chromosome Pairing / Q000235:genetics*; D004247:DNA / Q000096:biosynthesis* / Q000235:genetics; D004265:DNA Helicases; D004260:DNA Repair / Q000235:genetics*; D045643:DNA Repair Enzymes; D004277:DNA, Single-Stranded / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D051135:Rad51 Recombinase; D051721:Rad52 DNA Repair and Recombination Protein; D011995:Recombination, Genetic / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; C096063:MATA1 protein, S cerevisiae; C497197:RAD52 protein, S cerevisiae; C087191:RAD55 protein, S cerevisiae; D051721:Rad52 DNA Repair and Recombination Protein; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; C495151:RAD51 protein, S cerevisiae; D051135:Rad51 Recombinase; C075468:RAD54 protein, S cerevisiae; D004265:DNA Helicases; D045643:DNA Repair Enzymes