title: Effects of combination of different -10 hexamers and downstream sequences on stationary-phase-specific sigma factor sigma(S)-dependent transcription in Pseudomonas putida.
abstract: The main sigma factor activating gene expression, necessary in stationary phase and under stress conditions, is sigma(S). In contrast to other minor sigma factors, RNA polymerase holoenzyme containing sigma(S) (Esigma(S)) recognizes a number of promoters which are also recognized by that containing sigma(70) (Esigma(70)). We have previously shown that transposon Tn4652 can activate silent genes in starving Pseudomonas putida cells by creating fusion promoters during transposition. The sequence of the fusion promoters is similar to the sigma(70)-specific promoter consensus. The -10 hexameric sequence and the sequence downstream from the -10 element differ among these promoters. We found that transcription from the fusion promoters is stationary phase specific. Based on in vivo experiments carried out with wild-type and rpoS-deficient mutant P. putida, the effect of sigma(S) on transcription from the fusion promoters was established only in some of these promoters. The importance of the sequence of the -10 hexamer has been pointed out in several published papers, but there is no information about whether the sequences downstream from the -10 element can affect sigma(S)-dependent transcription. Combination of the -10 hexameric sequences and downstream sequences of different fusion promoters revealed that sigma(S)-specific transcription from these promoters is not determined by the -10 hexameric sequence only. The results obtained in this study indicate that the sequence of the -10 element influences sigma(S)-specific transcription in concert with the sequence downstream from the -10 box.
authors.affiliation: Department of Genetics, Institute of Molecular and Cell Biology, Estonian Biocentre and Tartu University, 51010 Tartu, Estonia.
authors.forename: E L
authors.initials: EL
authors.lastname: Ojangu
authors.forename: A
authors.initials: A
authors.lastname: Tover
authors.forename: R
authors.initials: R
authors.lastname: Teras
authors.forename: M
authors.initials: M
authors.lastname: Kivisaar
mesh_terms: D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D016958:Pseudomonas putida / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria; C106402:RNA polymerase Esigma(38); D012321:DNA-Directed RNA Polymerases