title: Analysis of gain-of-function mutants of an ATP-dependent regulator of Tn7 transposition.
abstract: The bacterial transposon Tn7 is distinguished by its unusual discrimination among targets, being particularly attracted to certain target DNA and actively avoiding other DNA. Tn7 transposition is mediated by the interaction of two alternative transposon-encoded target selection proteins, TnsD and TnsE, with a common core transposition machinery composed of the transposase (TnsAB) and an ATP-dependent DNA-binding protein TnsC. No transposition is observed with wild-type TnsABC. Here, we analyze the properties of two gain-of-function TnsC mutants that allow transposition in the absence of TnsD or TnsE. We find that these TnsC mutants have altered interactions with ATP and DNA that can account for their gain-of-function phenotype. We also show that TnsC is an ATPase and that it directly interacts with the TnsAB transposase. This work provides strong support to the view that TnsC and its ATP state are central to the control of Tn7 transposition.
authors.affiliation: Howard Hughes Medical Institute, Department of Molecular Biology & Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Stellwagen
authors.forename: N L
authors.initials: NL
authors.lastname: Craig
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D002384:Catalysis / Q000187:drug effects; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics / Q000502:physiology; D006868:Hydrolysis / Q000187:drug effects; D016254:Mutagenesis, Insertional / Q000187:drug effects; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics; D019895:Transposases / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; C098908:TnsA protein, E coli; C069633:TnsB protein, E coli; C074940:TnsC protein, E coli; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D019895:Transposases; D000251:Adenosine Triphosphatases