Gene Q antiterminator proteins of Escherichia coli phages 82 and lambda suppress pausing by RNA polymerase at a rho-dependent terminator and at other sites.
The Q genes of phages lambda and 82 encode transcription antiterminators that are active in vitro in a purified transcription system. Transcription termination is thought to involve two distinct steps: pausing of the transcription complex at the terminator and release of enzyme and RNA; either or both steps might be inhibited by Q protein. We show that Q-modified RNA polymerase pauses much less efficiently than does unmodified enzyme at the natural pause sites of a rho-dependent terminator as well as at other pause sites. This changed behavior can account for the termination properties of Q-modified RNA polymerase and reflects a fundamental alteration of the elongation properties of the enzyme.
Yang
X J
XJ
Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY 14853.
Roberts
J W
JW
D010582:Bacteriophage lambda / Q000235:genetics* / Q000378:metabolism; D003090:Coliphages / Q000235:genetics* / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D005796:Genes; D005809:Genes, Regulator; D005814:Genes, Viral; D012234:Rho Factor / Q000378:metabolism*; D013489:Suppression, Genetic; D013698:Templates, Genetic; D013728:Terminator Regions, Genetic; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000378:metabolism*
D012234:Rho Factor; D014157:Transcription Factors; D014764:Viral Proteins; D012321:DNA-Directed RNA Polymerases