Characterization of the transcriptional stimulatory properties of the Pseudomonas putida RapA protein
Autor: | Agnieszka Szalewska-Pałasz, Victoria Shingler, Eleonore Skärfstad, Robert Lyzen, Ewa Stec-Dziedzic |
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Rok vydání: | 2013 |
Předmět: |
Transcription
Genetic Biophysics medicine.disease_cause Biochemistry chemistry.chemical_compound Bacterial Proteins Structural Biology Transcription (biology) RNA polymerase Escherichia coli Genetics medicine Promoter Regions Genetic Molecular Biology Transcription factor Polymerase Sequence Homology Amino Acid biology Pseudomonas putida Escherichia coli Proteins RNA Promoter DNA-Directed RNA Polymerases Gene Expression Regulation Bacterial biology.organism_classification Molecular biology DNA-Binding Proteins chemistry biology.protein |
Zdroj: | Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms. 1829:219-230 |
ISSN: | 1874-9399 |
DOI: | 10.1016/j.bbagrm.2012.11.008 |
Popis: | RNA polymerase-associated factors can significantly affect its performance at specific promoters. Here we identified a Pseudomonas putida RNA polymerases-associated protein as a homolog of Escherichia coli RapA. We found that P. putida RapA stimulates the transcription from promoters dependent on a variety of σ-factors (σ(70), σ(S), σ(54), σ(32), σ(E)) in vitro. The level of stimulation varied from 2- to 10-fold, with the maximal effect observed with the σ(E)-dependent PhtrA promoter. Stimulation by RapA was apparent in the multi-round reactions and was modulated by salt concentration in vitro. However, in contrast to findings with E. coli RapA, P. putida RapA-mediated stimulation of transcription was also evident using linear templates. These properties of P. putida RapA were apparent using either E. coli- or P. putida-derived RNA polymerases. Analysis of individual steps of transcription revealed that P. putida RapA enhances the stability of competitor-resistant open-complexes formed by RNA polymerase at promoters. In vivo, P. putida RapA can complement the inhibitory effect of high salt on growth of an E. coli RapA null strain. However, a P. putida RapA null mutant was not sensitive to high salt. The in vivo effects of lack of RapA were only detectable for the σ(E)-PhtrA promoter where the RapA-deficiency resulted in lower activity. The presented characteristics of P. putida RapA indicate that its functions may extend beyond a role in facilitating RNA polymerase recycling to include a role in transcription initiation efficiency. |
Databáze: | OpenAIRE |
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