A role for H-NS in the thermo-osmotic regulation of virulence gene expression in Shigella flexneri.
The role of the hns gene (coding for the curved-DNA-binding protein H-NS) in the thermo-osmotic regulation of Shigella flexneri virulence gene transcription was investigated. Two structural genes, mxiC and icsB, which are transcribed divergently on the high-molecular-weight virulence plasmid, were found to be transcriptionally inhibited in cultures grown in a low-osmolarity medium, even at the inducing temperature. This repression was relieved by inactivation of the hns gene, establishing a role for hns in the osmotic as well as the thermal regulation of invasion gene expression. The physiological relevance of this finding is discussed.
Department of Biochemistry, University of Dundee, Scotland, United Kingdom.
M E
ME
Porter
C J
CJ
Dorman
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics; D006358:Hot Temperature; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D012763:Shigella flexneri / Q000235:genetics* / Q000472:pathogenicity*; D015398:Signal Transduction; D014158:Transcription, Genetic; D014774:Virulence / Q000235:genetics
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C031908:H-NS protein, bacteria