Related Experiment Video
Updated: Jul 30, 2026
09:28
In Vitro Transcription Assays and Their Application in Drug Discovery
Published on: September 20, 2016
Nus A is involved in transcriptional termination on lambda tI
R M Bermúdez-Cruz1, M J Chamberlin, C Montañez
1Departmento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N., Mexico City, D.F.C.P., Mexico.
Biochimie
|September 24, 1999
Summary
The lambda phage tI terminator
Area of Science:
- Molecular Biology
- Bacteriophage Genetics
Background:
- The lambda phage integrase (int) gene transcript is terminated by the tI terminator.
- Understanding transcription termination is crucial for gene regulation in bacteriophages.
Purpose of the Study:
- To investigate the factors influencing transcription termination at the lambda tI terminator.
- To determine the role of the NusA protein in tI terminator efficiency.
Main Methods:
- In vitro transcription assays using purified NusA protein.
- In vivo studies measuring readthrough transcripts via quantitative dot blot analysis in wild-type and nusA1 mutant strains.
Main Results:
- In vitro, tI terminator efficiency increased from 50% to 80% with NusA protein.
- In vivo, wild-type strains showed 80% efficiency, while nusA1 mutants exhibited 60% efficiency at non-permissive temperatures.
Conclusions:
- NusA protein significantly enhances the efficiency of the lambda tI transcriptional terminator.
- These findings indicate that NusA is a key factor involved in lambda tI-mediated transcription termination in vivo.
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