A direct link between the global regulator PhoP and the Csr regulon in Y. pseudotuberculosis through the small regulatory RNA CsrC.
In this study we investigated the influence of the global response regulator PhoP on the complex regulatory cascade controlling expression of early stage virulence genes of Yersinia pseudotuberculosis via the virulence regulator RovA. Our analysis revealed the following novel features: (1) PhoP activates expression of the CsrC RNA in Y. pseudotuberculosis, leading to activation of RovA synthesis through the CsrABC-RovM cascade, (2) activation of csrC transcription is direct and PhoP is shown to bind to two separate PhoP box-like sites, (3) PhoP-mediated activation results in transcription from two different promoters closely downstream of the PhoP binding sites, leading to two distinct CsrC RNAs, and (4) the stability of the CsrC RNAs differs significantly between the Y. pseudotuberculosis strains YPIII and IP32953 due to a 20 nucleotides insertion in CsrC(IP32953), which renders the transcript more susceptible to degradation. In summary, our study showed that PhoP-mediated influence on the regulatory cascade controlling the Csr system and RovA in Y. pseudotuberculosis varies within the species, suggesting that the Csr system is a focal point to readjust and adapt the genus to different hosts and reservoirs.
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Aaron M
AM
Nuss
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Franziska
F
Schuster
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Ann
A
Kathrin Heroven
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Wiebke
W
Heine
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Fabio
F
Pisano
Department of Molecular Infection Biology; Helmholtz Centre for Infection Research; Braunschweig, Germany.
Petra
P
Dersch
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D008954:Models, Biological; D011485:Protein Binding; D020871:RNA Stability; D012329:RNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D058727:RNA, Small Untranslated / Q000235:genetics* / Q000378:metabolism; D038621:Regulatory Sequences, Ribonucleic Acid; D014157:Transcription Factors / Q000235:genetics; D024363:Transcription Initiation Site; D015533:Transcriptional Activation; D014774:Virulence / Q000235:genetics; D015011:Yersinia pseudotuberculosis / Q000235:genetics* / Q000378:metabolism* / Q000472:pathogenicity; D015012:Yersinia pseudotuberculosis Infections / Q000382:microbiology
D001426:Bacterial Proteins; D012329:RNA, Bacterial; D058727:RNA, Small Untranslated; D038621:Regulatory Sequences, Ribonucleic Acid; C405626:RovA protein, Yersinia; C517503:RovM protein, Yersinia pseudotuberculosis; D014157:Transcription Factors; C061064:PhoP protein, Bacteria
Csr system; PhoP; RovA; Y. pseudotuberculosis; regulatory RNAs; virulence gene regulation