PMID:10760580
| Citation |
Rostoks, N, Park, S and Choy, HE (2000) Reiterative transcription initiation from galP2 promoter of Escherichia coli. Biochim. Biophys. Acta 1491:185-95 |
|---|---|
| Abstract |
The expression of gal operon in Escherichia coli is driven by two promoters, P1 and P2 separated by 5 bp. The transcription initiated from the P2 generates a large amount of abortive transcripts to produce a comparable amount of full-length transcript as P1 in vitro. In this study, we investigated the source of the abortive transcripts by employing a quantitative potassium permanganate footprinting method that determines the extent of open promoter complex formation. The extents of open promoter complex formation at the two gal promoters were about the same during the given reaction time while the amount of transcription initiation determined by in vitro transcription assay showed a considerable difference: several hundred-fold more transcription initiation from the P2 than the P1, most of which was abortive. Thus, it was concluded that the abortive transcripts are generated reiteratively by a small fraction of RNA polymerase. An in vitro transcription assay using an immobilized DNA template revealed that the fraction of RNA polymerase generating abortive transcripts never produces the full-length transcript and it remains bound to the promoter. We concluded that there are two kinds of RNA polymerase-promoter complexes formed at galP2, at least in vitro, productive complex and nonproductive complex; and, the nonproductive complex is responsible for generating large amount of abortive transcripts from the P2. |
| Links | |
| Keywords |
Carrier Proteins; Cyclic AMP Receptor Protein/pharmacology; DNA Footprinting; DNA-Directed RNA Polymerases/genetics; Escherichia coli/chemistry; Escherichia coli/genetics; Kinetics; Models, Molecular; Potassium Permanganate; Promoter Regions, Genetic; RNA/biosynthesis; Templates, Genetic; Transcription, Genetic/drug effects |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.