Concerted actions of a thermo-labile regulator and a unique intergenic RNA thermosensor control Yersinia virulence.

ABSTRACT: Expression of all Yersinia pathogenicity factors encoded on the virulence plasmid, including the yop effector and the ysc type III secretion genes, is controlled by the transcriptional activator LcrF in response to temperature. Here, we show that a protein- and RNA-dependent hierarchy of thermosensors induce LcrF synthesis at body temperature. Thermally regulated transcription of lcrF is modest and mediated by the thermo-sensitive modulator YmoA, which represses transcription from a single promoter located far upstream of the yscW-lcrF operon at moderate temperatures. The transcriptional response is complemented by a second layer of temperature-control induced by a unique cis-acting RNA element located within the intergenic region of the yscW-lcrF transcript. Structure probing demonstrated

SUBMITTER: Bohme K 

PROVIDER: S-EPMC3280987 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature