Transcriptional regulation of the Shigella flexneri icsp Promoter: Silencing and anti-silencing by H-NS and VirB
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چکیده
...................................................................................................................... iii ACKNOWLEDGMENTS .................................................................................................. v LIST OF FIGURES ........................................................................................................... ix LIST OF TABLES.............................................................................................................. x CHAPTER
منابع مشابه
VirB alleviates H-NS repression of the icsP promoter in Shigella flexneri from sites more than one kilobase upstream of the transcription start site.
The icsP promoter of Shigella spp. is repressed by H-NS and derepressed by VirB. Here, we show that an inverted repeat located between positions -1144 and -1130 relative to the icsP transcription start site is necessary for VirB-dependent derepression. The atypical location of this cis-acting site is discussed.
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In Shigella flexneri, expression of the plasmid-encoded virulence genes is regulated via a complex cascade involving DNA topology, specific transactivators, and the nucleoid-associated protein H-NS, which represses transcription under inappropriate environmental conditions. We have investigated the involvement of a second nucleoid-associated protein, integration host factor (IHF), in virulence ...
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