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Updated: Oct 7, 2025
11:19
Isolation of Translating Ribosomes Containing Peptidyl-tRNAs for Functional and Structural Analyses
Published on: February 25, 2011
20.1K
Insights into the ribosomal trans-translation rescue system: lessons from recent structural studies
Gaetano D'Urso1, Charlotte Guyomar1, Sophie Chat1
1Institut de Génétique et Développement de Rennes (IGDR), CNRS, Univ. Rennes, France.
The FEBS Journal
|January 11, 2022
Summary
Bacterial trans-translation, involving transfer-messenger RNA (tmRNA) and small protein B (SmpB), rescues stalled protein synthesis. This vital system tags incomplete proteins for degradation and recycles ribosomes, preventing cell death.
Area of Science:
- Molecular Biology
- Bacterial Physiology
- Protein Synthesis Regulation
Background:
- Ribosome stalling on stop-codon-less mRNA halts protein synthesis, posing a cellular risk.
- Bacteria employ trans-translation as a critical quality control mechanism to address this issue.
Purpose of the Study:
- To elucidate the molecular mechanism of bacterial trans-translation.
- To provide an updated structural view of the trans-translation system.
Main Methods:
- Utilized cryo-electron microscopy for high-resolution structural analysis.
- Investigated the synergistic action of transfer-messenger RNA (tmRNA) and small protein B (SmpB).
Main Results:
- Detailed the molecular steps involved in rescuing stalled ribosomes.
- Illustrated the tagging of incomplete peptides for degradation.
- Showcased the degradation of aberrant mRNAs and recycling of ribosomes.
Conclusions:
- Trans-translation is an essential bacterial system for maintaining proteostasis and cell viability.
- Recent structural insights have refined our understanding of the tmRNA-SmpB complex's function.
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