Repressor activity of the RpoS/σS-dependent RNA polymerase requires DNA binding - Institut Pasteur Access content directly
Journal Articles Nucleic Acids Research Year : 2015

Repressor activity of the RpoS/σS-dependent RNA polymerase requires DNA binding

Abstract

The RpoS/σS sigma subunit of RNA polymerase (RNAP) activates transcription of stationary phase genes in many Gram-negative bacteria and controls adaptive functions, including stress resistance, biofilm formation and virulence. In this study, we address an important but poorly understood aspect of σS-dependent control, that of a repressor. Negative regulation by σ S has been proposed to result largely from competition between σS and other σ factors for binding to a limited amount of core RNAP (E). To assess whether σS binding to E alone results in significant downregulation of gene expression by other σfactors, we characterized an rpoS mutant of Salmonella enterica serovar Typhimurium producing a σS protein proficient for EσS complex formation but deficient in promoter DNA binding. Genome expression profiling and physiological assays revealed that this mutant was defective for negative regulation , indicating that gene repression by σS requires its binding to DNA. Although the mechanisms of repression by σS are likely specific to individual genes and environmental conditions, the study of transcription downregulation of the succinate dehydrogenase operon suggests that σcompetition at the promoter DNA level plays an important role in gene repression by EσS .
Fichier principal
Vignette du fichier
Nucl. Acids Res.-2015-Lévi-Meyrueis-nar-gku1379 2.pdf (3.67 Mo) Télécharger le fichier
Origin : Publication funded by an institution
Loading...

Dates and versions

pasteur-01370752 , version 1 (23-09-2016)

Licence

Attribution - NonCommercial

Identifiers

Cite

Corinne Levi-Meyrueis, Véronique Monteil, Odile Sismeiro, Marie-Agnès Dillies, Annie Kolb, et al.. Repressor activity of the RpoS/σS-dependent RNA polymerase requires DNA binding. Nucleic Acids Research, 2015, 43 (3), pp.1456 - 1468. ⟨10.1093/nar/gku1379⟩. ⟨pasteur-01370752⟩
285 View
192 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More