title: Conversion of the omega subunit of Escherichia coli RNA polymerase into a transcriptional activator or an activation target.
abstract: Evidence obtained in both eukaryotes and prokaryotes indicates that arbitrary contacts between DNA-bound proteins and components of the transcriptional machinery can activate transcription. Here we demonstrate that the Escherichia coli omega protein, which copurifies with RNA polymerase, can function as a transcriptional activator when linked covalently to a DNA-binding protein. We show further that omega can function as an activation target when this covalent linkage is replaced by a pair of interacting polypeptides fused to the DNA-binding protein and to omega, respectively. Our findings imply that the omega protein is associated with RNA polymerase holoenzyme in vivo, and provide support for the hypothesis that contact between a DNA-bound protein and any component of E. coli RNA polymerase can activate transcription.
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Dove
authors.forename: A
authors.initials: A
authors.lastname: Hochschild
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; C111232:RNA polymerase omega subunit; D012321:DNA-Directed RNA Polymerases