Genetic analysis of bacteriophage lambdaN-dependent antitermination suggests a possible role for the RNA polymerase alpha subunit in facilitating specific functions of NusA and NusE.
A role for the Escherichia coli RNA polymerase alpha subunit in transcription antitermination dependent on bacteriophage lambda N protein has been previously inferred from the isolation of rpoA mutants that alter the efficiency of this process. This report describes studies on the efficiency of N-dependent transcription antitermination in a strain containing the rpoA341 mutation, which interferes with this process. The effect of mutations in genes coding for different Nus factors and/or plasmids overexpressing nus genes on bacteriophage lambda development in an E. coli rpoA341 host was examined. In addition, the effect of overproduction of the N protein in these genetic backgrounds was assessed. Analogous bacterial strains were employed to measure the efficiency of the antitermination process using the lacZ reporter gene under control of the lambda p(R) promoter, and containing the phage nutR region and the t( R1) terminator between the promoter and lacZ. The experimental results suggest interactions between components of the N-antitermination complex, which have been established biochemically, as well as additional functional relationships within the complex. Furthermore, the results indicate that amino acid substitution in the alpha subunit C-terminal domain encoded by the rpoA341 mutation may specifically disrupt the function of the NusA and NusE proteins. During this analysis, it was also found that the E. coli nusA1 mutant exhibits a conditional lethal phenotype.
Szalewska-Pałasz
Agnieszka
A
Department of Molecular Biology, University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland.
Strzelczyk
Barbara
B
Herman-Antosiewicz
Anna
A
Wegrzyn
Grzegorz
G
Thomas
Mark S
MS
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D010582:Bacteriophage lambda / Q000235:genetics; D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000821:virology; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D010445:Peptide Elongation Factors / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism*; D013728:Terminator Regions, Genetic; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D035602:Transcriptional Elongation Factors; D054334:Viral Regulatory and Accessory Proteins / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C059417:N protein, Bacteriophage lambda; D010445:Peptide Elongation Factors; D016601:RNA-Binding Proteins; D012269:Ribosomal Proteins; D014157:Transcription Factors; D035602:Transcriptional Elongation Factors; D054334:Viral Regulatory and Accessory Proteins; C064872:antiterminator proteins, Bacteria; C068727:nusA protein, E coli; C029537:ribosomal protein S10; D012321:DNA-Directed RNA Polymerases; C113275:RNA polymerase alpha subunit