An antitermination protein engages the elongating transcription apparatus at a promoter-proximal recognition site.
As a transcriptional activator, the N protein of phage lambda acts to suppress transcription termination by recognizing a promoter-proximal site, nut, which is separated from the terminators by thousands of base pairs. We demonstrate here that N interacts with the elongating RNA polymerase in transit through the boxB domain of nut. This interaction leads to the stable association of N as an integral component of the transcription apparatus. During subsequent elongation, N translocates along with polymerase through several defined terminators positioned beyond nut. Therefore, by being an operon-specific subunit of the transcription apparatus, N presumably prevents the interaction of polymerase with termination signals.
D001426:Bacterial Proteins / Q000378:metabolism / Q000502:physiology; D010582:Bacteriophage lambda / Q000235:genetics* / Q000502:physiology; D004926:Escherichia coli / Q000502:physiology; D005809:Genes, Regulator; D005814:Genes, Viral; D008957:Models, Genetic; D011401:Promoter Regions, Genetic; D012318:RNA Polymerase I / Q000378:metabolism; D013728:Terminator Regions, Genetic; D014157:Transcription Factors / Q000502:physiology*; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000502:physiology*
D001426:Bacterial Proteins; D014157:Transcription Factors; D014764:Viral Proteins; D012318:RNA Polymerase I