The NusA N-Terminal Domain Is Necessary and Sufficient for Enhancement of Transcriptional Pausing via Interaction with the RNA Exit Channel of RNA Polymerase
| Autor: | Dmitry G. Vassylyev, Kook Sun Ha, Robert Landick, Innokenti Toulokhonov |
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| Rok vydání: | 2010 |
| Předmět: |
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Molecular Transcription Genetic Protein Conformation Protein Data Bank (RCSB PDB) Regulator Biology Article chemistry.chemical_compound Protein structure Structural Biology RNA polymerase Intrinsic termination Transcriptional regulation Molecular Biology Terminator Regions Genetic Genetics Escherichia coli Proteins RNA DNA-Directed RNA Polymerases Peptide Elongation Factors Cell biology RNA Bacterial chemistry Antitermination Nucleic Acid Conformation Transcriptional Elongation Factors Transcription Factors |
| Zdroj: | Journal of Molecular Biology. 401:708-725 |
| ISSN: | 0022-2836 |
| Popis: | NusA is a core regulator of transcript elongation that is well conserved in bacteria and archaea. NusA interacts with elongating complexes and the nascent RNA transcript in ways that stimulate pausing and termination but can be switched to anti-pausing and anti-termination by other accessory proteins. The regulatory complexity of NusA likely depends on the presence of multiple discrete NusA domains, but it remains unclear which NusA domains possess which regulatory activity and how they interact with elongating RNA polymerase. We used a series of truncated NusA proteins to measure the effect of the NusA domains on transcriptional pausing and termination. We find that the N-terminal domain of NusA is necessary and sufficient for enhancement of transcriptional pausing and the other NusA domains contribute to NusA binding to elongating complexes. Stimulation of intrinsic termination requires higher concentrations of NusA, and involves both the N-terminal domain and other NusA domains. Using a tethered chemical protease in addition to protein-RNA crosslinking, we show that the NusA N-terminal domain contacts the RNA exit channel of RNA polymerase. Finally, we report evidence that the NusA N-terminal domain recognizes duplex RNA in the RNA exit channel. |
| Databáze: | OpenAIRE |
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