2006/12/12 by Padraig Deighan, Ann Hochschild · 1 citation
Environmental Science · Biochemistry, Genetics and Molecular Biology · #Bacteriophages and microbial interactions #Bacterial Genetics and Biotechnology #RNA and protein synthesis mechanisms
paper · pdf · doi:10.1111/j.1365-2958.2006.05563.x
openalex publication_date 2006/12/12 · openalex created_date 2016/06/24 · openalex updated_date 2026/06/24
The Q protein of bacteriophage lambda (lambdaQ) is a transcription anti-terminator required for the expression of the phage's late genes under the control of promoter P(R'). To effect terminator read-through, lambdaQ must gain access to RNA polymerase (RNAP) via a promoter-restricted pathway. In particular, lambdaQ modifies RNAP by binding a specific DNA site embedded in P(R') and interacting with RNAP in the context of a specific paused early elongation complex. The resultant lambdaQ-modified transcription elongation complex is competent to read through downstream termination signals. Here we use a chromatin-immunoprecipitation assay to test the hypothesis that lambdaQ functions as a stable component of the transcription elongation complex. Our results indicate that, in vivo, the lambdaQ-modified transcription elongation complex contains Q as a stably associated subunit. Furthermore, we find that in the physiologically relevant context of an induced lambda lysogen, Q remains stably associated with RNAP as it transcribes at least 22 kb of the phage late operon. Thus, our findings suggest that the promoter-specific pathway leading to lambdaQ-mediated terminator read-through results in the formation of a highly stable lambdaQ-containing transcription elongation complex capable of traversing the entire late operon.