PrfA, the transcriptional activator of virulence genes, is upregulated during interaction of Listeria monocytogenes with mammalian cells and in eukaryotic cell extracts.
Most virulence genes of Listeria monocytogenes are activated by the transcriptional regulator PrfA. Previous studies have shown that environmental parameters, such as temperature, pH, stress conditions and medium composition, affect the expression of PrfA and PrfA-dependent proteins. In this report, we demonstrate a threefold increase in PrfA protein synthesis during infection of mammalian cells, which correlates with the increased activity of the plcA promoter, the major prfA promoter. Increased PrfA synthesis begins when L. monocytogenes adheres to host cells. In addition, we show that the observed induction of PrfA during the interaction of L. monocytogenes with mammalian cells can be reproduced in vitro using total cell extracts. Our data suggest a role for host proteinase K-sensitive protein(s) in PrfA upregulation.
Renzoni
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A
Unité des Interactions Bactéries-Cellules, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
Cossart
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P
Dramsi
S
S
D000818:Animals; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D015153:Blotting, Western; D002457:Cell Extracts; D002460:Cell Line; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D008087:Listeria / Q000235:genetics / Q000378:metabolism; D008089:Listeria monocytogenes / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D051379:Mice; D010454:Peptide Termination Factors; D011401:Promoter Regions, Genetic; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic; D015854:Up-Regulation; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D002457:Cell Extracts; D010454:Peptide Termination Factors; D015534:Trans-Activators