title: Holliday junction-binding peptides inhibit distinct junction-processing enzymes.
abstract: Holliday junctions (HJ) are the central intermediates in both homologous recombination and site-specific recombination performed by tyrosine recombinases such as the bacteriophage lambda Integrase (Int) protein. Previously, our lab identified peptide inhibitors of Int-mediated recombination that prevent the resolution of HJ intermediates. We now show that two of these inhibitors bind HJ DNA in the square-planar conformation even in the absence of Int protein. The peptides prevent unwinding of branched DNA substrates by the RecG helicase of Escherichia coli and interfere with the resolution of HJ substrates by the RuvABC complex. Our results suggest that these peptides target all proteins that process HJ in the square-planar conformation. These inhibitors should be extremely useful for dissecting homologous recombination and recombination-dependent repair in vitro and in vivo.
authors.affiliation: Center for Microbial Sciences and Department of Biology, San Diego State University, San Diego, CA 92182-4614, USA.
authors.forename: Kevin V
authors.initials: KV
authors.lastname: Kepple
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Boldt
authors.forename: Anca M
authors.initials: AM
authors.lastname: Segall
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D001483:Base Sequence; D004265:DNA Helicases / Q000378:metabolism; D045566:DNA, Cruciform / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004706:Endodeoxyribonucleases / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism; D020128:Inhibitory Concentration 50; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D011196:Potassium Permanganate / Q000494:pharmacology; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry; D011995:Recombination, Genetic
chemical_list: D001426:Bacterial Proteins; D045566:DNA, Cruciform; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D010455:Peptides; D011506:Proteins; C061260:RuvB protein, Bacteria; C069806:ruvC protein, E coli; D011196:Potassium Permanganate; C071446:RecG protein, E coli; D004706:Endodeoxyribonucleases; C071059:Holliday junction DNA helicase, E coli; D004265:DNA Helicases