标题:NusA protein is necessary and sufficient in vitro for phage lambda N gene product to suppress a rho-independent terminator placed downstream of nutL
期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1988
卷号:85
期号:8
页码:2494-2498
DOI:10.1073/pnas.85.8.2494
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Transcription antitermination by phage lambda N protein is reproduced in vitro solely with purified components. We have placed a strong rho-independent terminator, lambda tR', in the PL operon about 200 base pairs downstream from the N-recognition site, nutL, and have monitored terminated and run-off transcripts produced by single-round transcription of linear plasmids. In the presence of NusA, one of several host factors implicated in antitermination, N is found to virtually abolish termination at tR'. N is unable to suppress termination if the terminator is preceded by a defective nut site. Thus, during transcription through the nut site, N and NusA can modify RNA polymerase to a termination-resistant form in the absence of any other accessory factor.