title: Mapping of RNA polymerase residues that interact with bacteriophage Xp10 transcription antitermination factor p7.
abstract: Bacteriophage Xp10-encoded transcription factor p7 interacts with host Xanthomonas oryzae RNA polymerase beta' subunit and prevents both promoter recognition by the RNA polymerase holoenzyme and transcription termination by the RNA polymerase core. P7 does not bind to and has no effect on RNA polymerase from Escherichia coli. Here, we use a combination of biochemical and genetic methods to map the p7 interaction site to within four beta' amino acid residues at the N terminus of X. oryzae RNAP beta'. The interaction site is located in an area that is close to the promoter spacer in the open complex and to the upstream boundary of the transcription bubble in the elongation complex, providing a possible explanation of how a small protein can affect both transcription initiation and termination by binding to the same RNA polymerase site.
authors.affiliation: Waksman Institute for Microbiology Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
authors.forename: Yulia
authors.initials: Y
authors.lastname: Yuzenkova
authors.forename: Nikolay
authors.initials: N
authors.lastname: Zenkin
authors.forename: Konstantin
authors.initials: K
authors.lastname: Severinov
mesh_terms: D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010957:Plasmids; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013728:Terminator Regions, Genetic; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D014974:Xanthomonas / Q000201:enzymology
chemical_list: D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D012321:DNA-Directed RNA Polymerases