An analysis of the role of host factors in transcription antitermination in vitro by the Q protein of coliphage lambda
- 1 June 1990
- journal article
- research article
- Published by Springer Nature in Molecular Genetics and Genomics
- Vol. 222 (1) , 152-156
- https://doi.org/10.1007/bf00283037
Abstract
Summary We used two different approaches to study the requirement for Escherichia coli Nus factors for the activity of bacteriophage lambda late antiterminator Q. Using an in vitro coupled transcription-translation assay, based on Q-dependent synthesis of galactokinase from a pR′-tR′-galK template, we showed that mutations in the host nusB and nusE genes do not affect Q activity. A mutation in nusA (nusAl) only partially affects Q action at all temperatures tested. Defective Q function in the nusAl mutant extract could be restored by the addition of pure NusA but not by excess Q. In a pure transcription system, measurement of the run-off transcript produced by Q-mediated suppression of tR′ revealed that NusA is greatly stimulatory to Q activity, whereas NusB and S10, in the presence or absence of NusA, have no effect. Unidentified E. coli factor(s) present in an S30 extract efficiently suppress the natural pausing by RNA polymerase at + 15, + 16 of pR′ without affecting Q activity. These results show that NusA is the only host protein that directly participates in Q function.Keywords
This publication has 17 references indexed in Scilit:
- An elongation control particle containing the N gene transcriptional antitermination protein of bacteriophage lambdaCell, 1987
- An antitermination protein engages the elongating transcription apparatus at a promoter-proximal recognition siteCell, 1987
- Isolation and properties of transcribing ternary complexes of Escherichia coli RNA polymerase positioned at a single template baseJournal of Molecular Biology, 1987
- Phage lambda gene Q antiterminator recognizes RNA polymerase near the promoter and accelerates it through a pause siteCell, 1985
- Evidence that ribosomal protein S10 itself is a cellular component necessary for transcription antitermination by phage lambda N protein.Proceedings of the National Academy of Sciences, 1985
- nusB: a protein factor necessary for transcription antitermination in vitro by phage lambda N gene product.Proceedings of the National Academy of Sciences, 1984
- Transcription antitermination in vitro by lambda N gene product: Requirement for a phage nut site and the products of host nusA, nusB, and nusE genesCell, 1984
- Evidence that a nucleotide sequence, “boxA,” is involved in the action of the NusA proteinCell, 1983
- The phage λ Q gene product: Activity of a transcription antiterminator in vitroCell, 1982
- Interaction of the sigma factor and the nusA gene protein of E. coli with RNA polymerase in the initiation-termination cycle of transcriptionCell, 1981