Suppressor mutations in rpoA suggest that OmpR controls transcription by direct interaction with the alpha subunit of RNA polymerase.
We have isolated mutations in rpoA, the gene encoding the alpha subunit of RNA polymerase, that specifically affect transcriptional control by OmpR and EnvZ, the two-component regulatory system that controls porin gene expression in Escherichia coli. Characterization of these mutations and a previously isolated rpoA allele suggests that both positive and negative regulation of porin gene transcription involves a direct interaction between OmpR and RNA polymerase through the alpha subunit. Several of the rpoA mutations cluster in the carboxy-terminal portion of the alpha protein, further suggesting that it is this domain of alpha that is involved in interaction with OmpR and perhaps other transcriptional regulators as well.
Slauch
J M
JM
Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, New Jersey 08544-1014.
Russo
F D
FD
Silhavy
T J
TJ
D000483:Alleles; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D012321:DNA-Directed RNA Polymerases / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005838:Genotype; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction; D018272:Porins; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D001425:Bacterial Outer Membrane Proteins; D046911:Macromolecular Substances; D009838:Oligodeoxyribonucleotides; D018272:Porins; D011993:Recombinant Fusion Proteins; D012321:DNA-Directed RNA Polymerases; D001616:beta-Galactosidase