title: Crystal structure of a Rad51 filament.
abstract: Rad51, the major eukaryotic homologous recombinase, is important for the repair of DNA damage and the maintenance of genomic diversity and stability. The active form of this DNA-dependent ATPase is a helical filament within which the search for homology and strand exchange occurs. Here we present the crystal structure of a Saccharomyces cerevisiae Rad51 filament formed by a gain-of-function mutant. This filament has a longer pitch than that seen in crystals of Rad51's prokaryotic homolog RecA, and places the ATPase site directly at a new interface between protomers. Although the filament exhibits approximate six-fold symmetry, alternate protein-protein interfaces are slightly different, implying that the functional unit of Rad51 within the filament may be a dimer. Additionally, we show that mutation of His352, which lies at this new interface, markedly disrupts DNA binding.
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA.
authors.forename: Adam B
authors.initials: AB
authors.lastname: Conway
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Lynch
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Gary S
authors.initials: GS
authors.lastname: Fortin
authors.forename: Cindy W
authors.initials: CW
authors.lastname: Fung
authors.forename: Lorraine S
authors.initials: LS
authors.lastname: Symington
authors.forename: Phoebe A
authors.initials: PA
authors.lastname: Rice
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004249:DNA Damage; D004268:DNA-Binding Proteins / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008958:Models, Molecular; D009154:Mutation; D010766:Phosphorylation; D011485:Protein Binding; D011487:Protein Conformation; D051135:Rad51 Recombinase; D011938:Rec A Recombinases / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013997:Time Factors; D014443:Tyrosine / Q000737:chemistry
chemical_list: D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D014443:Tyrosine; D006639:Histidine; D000255:Adenosine Triphosphate; D004247:DNA; C495151:RAD51 protein, S cerevisiae; D051135:Rad51 Recombinase; D011938:Rec A Recombinases; D000251:Adenosine Triphosphatases