title: RecA dimers serve as a functional unit for assembly of active nucleoprotein filaments.
abstract: All RecA-like recombinase enzymes catalyze DNA strand exchange as elongated filaments on DNA. Despite numerous biochemical and structural studies of RecA and the related Rad51 and RadA proteins, the unit oligomer(s) responsible for nucleoprotein filament assembly and coordinated filament activity remains undefined. We have created a RecA fused dimer protein and show that it maintains in vivo DNA repair and LexA co-protease activities, as well as in vitro ATPase and DNA strand exchange activities. Our results support the idea that dimeric RecA is an important functional unit both for assembly of nucleoprotein filaments and for their coordinated activity during the catalysis of homologous recombination.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, Aaron Lazare Research Building, 364 Plantation Street, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Forget
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Kudron
authors.forename: Dharia A
authors.initials: DA
authors.lastname: McGrew
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Calmann
authors.forename: Celia A
authors.initials: CA
authors.lastname: Schiffer
authors.forename: Kendall L
authors.initials: KL
authors.lastname: Knight
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D019281:Dimerization; D009698:Nucleoproteins / Q000378:metabolism* / Q000648:ultrastructure; D011938:Rec A Recombinases / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: D009698:Nucleoproteins; D011993:Recombinant Fusion Proteins; D011938:Rec A Recombinases; D000251:Adenosine Triphosphatases