Co-ordinate expression of virulence genes by ToxR in Vibrio cholerae.
Evolution of complex regulatory pathways that control virulence factor expression in pathogenic bacteria indicates the importance to these organisms of being able to distinguish time and place. In the human intestinal pathogen Vibrio cholerae, control over many virulence genes identified to date is the responsibility of the ToxR protein. ToxR, in conjunction with a second regulatory protein called ToxS, directly activates the genes encoding the cholera toxin; other ToxR regulated genes are not activated directly by ToxR. For some of these genes, ToxR manifests its control through another activator called ToxT. Expression of toxT, which encodes a member of the AraC family of bacterial transcriptional activators, is ToxR dependent and is modulated by in vitro growth conditions that modulate expression of the ToxR virulence regulon. Thus, as in other regulatory circuits, co-ordinate expression of several genes in V. cholerae results from the activity of a cascading system of regulatory factors.
DiRita
V J
VJ
Unit for Laboratory Animal Medicine, University of Michigan Medical School, Ann Arbor 48109-0614.
D001426:Bacterial Proteins; D002772:Cholera Toxin / Q000235:genetics*; D004269:DNA, Bacterial / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008957:Models, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014734:Vibrio cholerae / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D014774:Virulence / Q000235:genetics
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D014157:Transcription Factors; C499324:toxR protein, Vibrio cholerae; C066719:toxR protein, bacteria; D002772:Cholera Toxin