The β-propeller gene Rv1057 of Mycobacterium tuberculosis has a complex promoter directly regulated by both the MprAB and TrcRS two-component systems - 27/12/11
Summary |
The β-propeller gene Rv1057 of Mycobacterium tuberculosis is activated by envelope stress and was first characterized as a regulatory target of the TrcRS two-component system (TCS). Rv1057 expression is repressed by TrcRS, and the Rv1057 proximal promoter contains a TrcR binding site. In this study, we determined that Rv1057 is also directly regulated by MprAB, a TCS associated with envelope stress. Multiple potential MprA binding sites (MprA boxes) were identified in the 1 kb intergenic region upstream of Rv1057, and four sites were shown to bind MprA. Although MprA boxes were found in the proximal promoter, analyses suggest that MprA and TrcR do not compete for binding in this region. An MprAB-dependent, detergent-inducible transcriptional start point for Rv1057 was identified downstream of the MprA boxes, and a second TrcR binding site and small ORF of the 13E12 family were discovered in the distal promoter. MprAB was required for activation of Rv1057 during growth in macrophages and under detergent stress, and lacZ promoter constructs suggest the entire intergenic region is utilized during MprAB-dependent activation of Rv1057. These findings indicate that Rv1057 has an extensive and complex promoter, and provide evidence for coordinated regulation of stress response genes by TCSs.
Le texte complet de cet article est disponible en PDF.Keywords : Mycobacterium, Two-component, Regulation, Envelope stress
Plan
While our manuscript was under review, the Zahrt laboratory reported that MprAB and DosRST coregulate the Rv0081-Rv0088 operon (He H, Bretl DJ et al., 2011, J. Bact. 193:5105-5118), providing further evidence for coordinated regulation of stress response genes by TCSs. |
Vol 91 - N° S1
P. S142-S149 - décembre 2011 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
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