Curation Information

The Pseudomonas aeruginosa global regulator VqsR directly inhibits QscR to control quorum-sensing and virulence gene expression.;Liang H, Deng X, Ji Q, Sun F, Shen T, He C;Journal of bacteriology 2012 Jun; 194(12):3098-108 [22505688]
VqsR [Q9I0P6, view regulon]
Reported TF sp.
Pseudomonas aeruginosa PAO1
Reported site sp.
Pseudomonas aeruginosa PAO1
Created by
Dinara Sagitova
Curation notes

Experimental Process

EMSA analysis showed that VqsR binds the qscR promoter. DNase I footprinting assay showed that VqsR binds to a region in the qscR promoter that contains an 18-bp inverted repeat motif. EMSA analysis showed that VqsR binding to the qscR promoter was abolished when this IR motif was deleted. A site-directed mutagenesis of the putative VqsR binding site further confirmed that the sequence of the inverted repeat motif is recognized by VqsR. A qscR promoter-lux fusion assay in a WT PAO1 and a vqsR mutant showed that VqsR negatively regulates qscR expression. Further, VqsR-regulated IR sequence was used to perform a genome wide search of the P. aeruginosa for additional VqsR-regulated promoters. The identified promoters were verified by performing EMSAs.

Transcription Factor Binding Sites


Gene Regulation

Regulated genes for each binding site are displayed below. Gene regulation diagrams show binding sites, positively-regulated genes, negatively-regulated genes, both positively and negatively regulated genes, genes with unspecified type of regulation. For each indvidual site, experimental techniques used to determine the site are also given.

Site sequence Regulated genes Gene diagram Experimental techniques TF function TF type