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Translational regulation by Hfq-Crc assemblies emerges from polymorphic ribonucleoprotein folding
Tom Dendooven1, Elisabeth Sonnleitner2, Udo Bläsi2
1Department of Biochemistry, University of Cambridge, Cambridge, UK.
The EMBO Journal
|December 12, 2022
Summary
The bacterial RNA chaperone Hfq and its partner Crc form diverse protein-RNA structures to regulate gene expression in Pseudomonas aeruginosa. This structural variety allows precise control over many genes using minimal components.
Area of Science:
- Bacterial gene regulation
- Molecular biology
- Structural biology
Background:
- The Hfq protein is crucial for post-transcriptional control of numerous genes in Pseudomonas aeruginosa.
- Understanding how Hfq regulates diverse genes is a significant challenge.
Purpose of the Study:
- To elucidate the structural basis of Hfq-mediated gene regulation in Pseudomonas aeruginosa.
- To investigate the role of the Crc protein in Hfq-RNA complex formation.
Main Methods:
- Cryo-electron microscopy (cryo-EM) was used to determine the structures of Hfq-Crc assemblies.
- Analysis of higher-order assemblies on target mRNA control regions.
Main Results:
- Hfq and Crc form mRNA-specific quaternary architectures.
- Assembly structures depend on protein-protein interactions and RNA sequence recognition.
- Structural polymorphism enables selective translational repression of target mRNAs.
Conclusions:
- The structural adaptability of Hfq-Crc ribonucleoprotein complexes underlies complex gene regulation.
- This system demonstrates evolutionary efficiency using limited protein components and RNA features.
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