Structure of RNA polymerase bound to ribosomal 30S subunit
- University of Massachusetts Medical School, United States
- New York University School of Medicine, United States
- Janelia Research Campus, Howard Hughes Medical Institute, United States
Abstract
In bacteria, mRNA transcription and translation are coupled to coordinate optimal gene expression and maintain genome stability. Coupling is thought to involve direct interactions between RNA polymerase (RNAP) and the translational machinery. We present cryo-EM structures of E. coli RNAP core bound to the small ribosomal 30S subunit. The complex is stable under cell-like ionic conditions, consistent with functional interaction between RNAP and the 30S subunit. The RNA exit tunnel of RNAP aligns with the Shine-Dalgarno-binding site of the 30S subunit. Ribosomal protein S1 forms a wall of the tunnel between RNAP and the 30S subunit, consistent with its role in directing mRNAs onto the ribosome. The nucleic-acid-binding cleft of RNAP samples distinct conformations, suggesting different functional states during transcription-translation coupling. The architecture of the 30S•RNAP complex provides a structural basis for co-localization of the transcriptional and translational machineries, and inform future mechanistic studies of coupled transcription and translation.
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Article and author information
Author details
Nikolaus Grigorieff
Andrei A Korostelev
Funding
National Institutes of Health (GM106105)
- Andrei A Korostelev
National Institutes of Health (GM107465)
- Andrei A Korostelev
National Institutes of Health (GM107329)
- Evgeny Nudler
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Rachel Green, Johns Hopkins School of Medicine, United States
Version history
- Received: May 11, 2017
- Accepted: October 11, 2017
- Accepted Manuscript published: October 13, 2017 (version 1)
- Version of Record published: October 24, 2017 (version 2)
Copyright
© 2017, Demo et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structure of RNA polymerase bound to ribosomal 30S subunit
eLife 6:e28560.
https://doi.org/10.7554/eLife.28560
Further reading
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