title: Multiple interfaces between a serine recombinase and an enhancer control site-specific DNA inversion.
abstract: Serine recombinases are often tightly controlled by elaborate, topologically-defined, nucleoprotein complexes. Hin is a member of the DNA invertase subclass of serine recombinases that are regulated by a remote recombinational enhancer element containing two binding sites for the protein Fis. Two Hin dimers bound to specific recombination sites associate with the Fis-bound enhancer by DNA looping where they are remodeled into a synaptic tetramer competent for DNA chemistry and exchange. Here we show that the flexible beta-hairpin arms of the Fis dimers contact the DNA binding domain of one subunit of each Hin dimer. These contacts sandwich the Hin dimers to promote remodeling into the tetramer. A basic region on the Hin catalytic domain then contacts enhancer DNA to complete assembly of the active Hin tetramer. Our results reveal how the enhancer generates the recombination complex that specifies DNA inversion and regulates DNA exchange by the subunit rotation mechanism. DOI:http://dx.doi.org/10.7554/eLife.01211.001.
authors.affiliation: Department of Biological Chemistry, David Geffen School of Medicine , University of California, Los Angeles , Los Angeles , United States.
authors.forename: Meghan M
authors.initials: MM
authors.lastname: McLean
authors.forename: Yong
authors.initials: Y
authors.lastname: Chang
authors.forename: Gautam
authors.initials: G
authors.lastname: Dhar
authors.forename: John K
authors.initials: JK
authors.lastname: Heiss
authors.forename: Reid C
authors.initials: RC
authors.lastname: Johnson
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D004254:DNA Nucleotidyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004278:DNA, Superhelical; D004742:Enhancer Elements, Genetic; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D035021:Factor For Inversion Stimulation Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D055503:Protein Multimerization; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D019779:Salmonella enterica / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004278:DNA, Superhelical; D035021:Factor For Inversion Stimulation Protein; D011994:Recombinant Proteins; D004254:DNA Nucleotidyltransferases; C059997:Hin recombinase
keywords: DNA strand exchange; E. coli; Salmonella enterica; recombinational enhancer; serine recombinase; site-specific DNA recombination; synaptic complex