title: Suppressor mutations in rpoA suggest that OmpR controls transcription by direct interaction with the alpha subunit of RNA polymerase.
abstract: 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.
authors.affiliation: Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, New Jersey 08544-1014.
authors.forename: J M
authors.initials: JM
authors.lastname: Slauch
authors.forename: F D
authors.initials: FD
authors.lastname: Russo
authors.forename: T J
authors.initials: TJ
authors.lastname: Silhavy
mesh_terms: 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
chemical_list: D001425:Bacterial Outer Membrane Proteins; D046911:Macromolecular Substances; D009838:Oligodeoxyribonucleotides; D018272:Porins; D011993:Recombinant Fusion Proteins; D012321:DNA-Directed RNA Polymerases; D001616:beta-Galactosidase