Suppressor Mutations in rpoA Suggest that OmpR Controls Transcription by Direct Interaction with the a Subunit of RNA Polymerase
نویسندگان
چکیده
We have isolated mutations in rpoA, the gene encoding the a 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 a subunit. Several of the rpoA mutations cluster in the carboxy-terminal portion of the a protein, further suggesting that it is this domain of a that is involved in interaction with OmpR and perhaps other transcriptional regulators as well.
منابع مشابه
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 transc...
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