title: An in vitro assay for monitoring the formation and branch migration of holliday junctions mediated by a eukaryotic recombinase.
abstract: DNA strand exchange is a core reaction of homologous recombination directly catalyzed by Rad51/Dmc1 RecA family recombinases in eukaryotes. This reaction proceeds through the formation of several DNA intermediates. The X-shaped four-way DNA structure known as a Holliday junction (HJ) is a central intermediate in homologous recombination. Genetic and biochemical studies indicate that the HJ is important for the production of crossover-type recombinants, which are reciprocal exchange products. According to a recombination model for the repair of DNA double-strand breaks, the formation of HJs requires a reciprocal duplex-duplex DNA exchange known as the DNA four-strand exchange reaction. In vitro analyses using purified recombination proteins and model DNA substrates provide a mechanistic insight into the DNA strand exchange reaction, including the steps leading to the formation and branch migration of Holliday junctions.
authors.affiliation: Cancer Research UK, London Research Institute, 44, Lincoln's Inn Fields, London, WC2A 3LY, UK. yasuto.murayama@cancer.org.uk
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Murayama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwasaki
mesh_terms: D053903:DNA Breaks, Double-Stranded; D053904:DNA Breaks, Single-Stranded; D045566:DNA, Cruciform / Q000235:genetics*; D006801:Humans; D051135:Rad51 Recombinase / Q000235:genetics / Q000378:metabolism; D011938:Rec A Recombinases / Q000235:genetics / Q000378:metabolism; D045522:Recombinases / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics*
chemical_list: D045566:DNA, Cruciform; D045522:Recombinases; D051135:Rad51 Recombinase; D011938:Rec A Recombinases