Antagonistic involvement of FIS and H-NS proteins in the transcriptional control of hns expression.
Gel shift and DNase I footprinting experiments showed that Escherichia coli FIS (factor for inversion stimulation) protein binds to at least seven sites in the promoter region of hns. These sites extend from -282 to +25 with two sites, closely flanking the DNA bend located at -150 from the transcriptional startpoint, partly overlapping the H-NS binding sites involved in the transcriptional autorepression of hns. The interplay between FIS, H-NS and the hns promoter region were studied by examining the effects of FIS and H-NS on in vitro transcription of hns-cat fusions, as well as looking at the effect of FIS on preformed complexes containing H-NS and a DNA fragment derived from the hns promoter region. Taken together, our data suggest that in the cell, FIS and H-NS interact with the promoter region of hns and influence their respective interactions (possibly competing for the same binding site), eliciting antagonistic effects so that an interplay between these proteins might contribute to the transcriptional control of hns.
Falconi
M
M
Department of Biology, University of Camerino, Italy.
Brandi
A
A
La Teana
A
A
Gualerzi
C O
CO
Pon
C L
CL
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000378:metabolism*; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D035021:Factor For Inversion Stimulation Protein; D015964:Gene Expression Regulation, Bacterial; D034982:Integration Host Factors; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D014158:Transcription, Genetic
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D035021:Factor For Inversion Stimulation Protein; C031908:H-NS protein, bacteria; D034982:Integration Host Factors; C440502:integration host factor, E coli