Architectural principles for Hfq/Crc-mediated regulation of gene expression
- University of Cambridge, United Kingdom
- University of Vienna, Austria
- MRC Laboratory of Molecular Biology, United Kingdom
Abstract
In diverse bacterial species, the global regulator Hfq contributes to post-transcriptional networks that control expression of numerous genes. Hfq of the opportunistic pathogen Pseudomonas aeruginosa inhibits translation of target transcripts by forming a regulatory complex with the catabolite repression protein Crc. This repressive complex acts part of an intricate mechanism of preferred nutrient utilisation. We describe high-resolution cryo-EM structures of the assembly of Hfq and Crc bound to the translation initiation site of a target mRNA. The core of the assembly is formed through interactions of two cognate RNAs, two Hfq hexamers and a Crc pair. Additional Crc protomers are recruited to the core to generate higher-order assemblies with demonstrated regulatory activity in vivo. This study reveals how Hfq cooperates with a partner protein to regulate translation, and provides a structural basis for an RNA code that guides global regulators to interact cooperatively and regulate different RNA targets.
Data availability
CryoEM data have been deposited
Article and author information
Author details
Funding
Wellcome Trust (200873/Z/16/Z)
- Ben F Luisi
Austrian Science Fund (P28711-B22)
- Udo Blasi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Anna Marie Pyle, Yale University, United States
Version history
- Received: October 26, 2018
- Accepted: February 11, 2019
- Accepted Manuscript published: February 13, 2019 (version 1)
- Version of Record published: March 18, 2019 (version 2)
Copyright
© 2019, Pei 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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Architectural principles for Hfq/Crc-mediated regulation of gene expression
eLife 8:e43158.
https://doi.org/10.7554/eLife.43158
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