Role of activating region 1 of Escherichia coli FNR protein in transcription activation at class II promoters.
FNR is an Escherichia coli transcription factor that activates gene expression in response to anaerobiosis at a large number of promoters by making direct contacts with RNA polymerase. At class II FNR-dependent promoters, where the DNA site for FNR overlaps the -35 element, activating region 1 of FNR is proposed to interact with the C-terminal domain of the RNA polymerase alpha-subunit. Using a model class II FNR-dependent promoter, FF(-41.5), we have performed in vivo and in vitro experiments to investigate the role of this interaction. Our results show that FNR, carrying substitutions in activating region 1, is compromised in its ability to promote open complex formation and thus to activate transcription. Abortive initiation assays were used to assess the contribution of activating region 1 of FNR to open complex formation. A new method for the purification of the FNR protein is also described.
Wing
H J
HJ
School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom. hwing@hsph.harvard.edu
Green
J
J
Guest
J R
JR
Busby
S J
SJ
D001426:Bacterial Proteins / Q000502:physiology*; D003850:Deoxyribonuclease I / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D005802:Genes, MHC Class II; D006493:Heparin / Q000494:pharmacology; D007506:Iron-Sulfur Proteins / Q000502:physiology*; D011196:Potassium Permanganate / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D015533:Transcriptional Activation
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C060704:FNR protein, E coli; D007506:Iron-Sulfur Proteins; D011196:Potassium Permanganate; D006493:Heparin; D003850:Deoxyribonuclease I