title: IHF is a trans-acting factor implicated in the regulation of the proU P2 promoter.
abstract: IHF is a protein of the bacterial nucleoid proteins (NAPs for nucleoid-associated proteins) involved in DNA structuring and transcription regulation. In vivo interplay between different NAPs determines selectively the expression rate of many genes. Here, we show that IHF is a trans-acting factor implicated directly in the regulation of the proU promoter of Escherichia coli by binding specifically and solely around the promoter box. proU expression is mainly under the repression effect of another NAP, H-NS. We show that IHF binding to proU organize the promoter DNA local structure in a completely different way than H-NS binding. Thus, we propose that the partial alleviation of H-NS repression is mediated by the promoter structure modification.
authors: LBPA, ENS Cachan, CNRS, F-94235 Cachan, France ahmad.khodr@pasteur.fr.
authors: Ahmad
authors: A
authors: Khodr
authors: LBPA, ENS Cachan, CNRS, F-94235 Cachan, France.
authors: Victoria
authors: V
authors: Fairweather
authors: LBPA, ENS Cachan, CNRS, F-94235 Cachan, France.
authors: Emeline
authors: E
authors: Bouffartigues
authors: LBPA, ENS Cachan, CNRS, F-94235 Cachan, France.
authors: Sylvie
authors: S
authors: Rimsky
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D034982:Integration Host Factors / Q000235:genetics* / Q000378:metabolism*; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015534:Trans-Activators; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C031908:H-NS protein, bacteria; D034982:Integration Host Factors; D015534:Trans-Activators; C440502:integration host factor, E coli
keywords: H-NS; IHF; NAPs; osmoregulation; proU