Related Experiment Video
Updated: Jul 8, 2026

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Poising of Escherichia coli RNA polymerase and its release from the sigma 38 C-terminal tail for osmY transcription
Adam Z Rosenthal1, Youngbae Kim, Jay D Gralla
1Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA.
Abstract:
Bacteria must adapt their transcription to overcome the osmotic stress associated with the gastrointestinal tract of their host. This requires the sigma 38 (rpoS) form of RNA polymerase. Here, chromatin immunoprecipitation experiments show that activation is associated with a poise-and-release mechanism in vivo. A C-terminal tail unique among sigma factors is shown to be required for in vivo recruitment of RNA polymerase to the promoter region prior to osmotic shock. C-terminal domain tail-dependent transcription in vivo can be mimicked by using the intracellular signaling molecule potassium glutamate in vitro. Following signaling, the barrier to elongation into the gene body is overcome and RNA polymerase is released to produce osmY mRNA.
More Related Videos
Related Concept Videos
Bacterial Transcription
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Transcription in Prokaryotes
Transcription Initiation
The promoters and enhancers and their accessory proteins allow tight regulation of...
Coordination of Gene Expression Processes in Bacteria

