Related Experiment Video
Updated: Jul 9, 2026
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Assessment of Selective mRNA Translation in Mammalian Cells by Polysome Profiling
Published on: October 28, 2014
Profiling of terminating ribosomes reveals translational control at stop codons
Longfei Jia1, Yuanhui Mao1, Saori Uematsu1
1Division of Nutritional Sciences, Cornell University, Ithaca, United States.
Elife
|July 7, 2026
Summary
Ribosome pausing at stop codons is variable and influenced by mRNA sequences. This pausing impacts protein synthesis accuracy, affecting protein C-terminal extensions and showing cell-specific patterns.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Protein synthesis termination is crucial for proteome integrity.
- The dynamics and fidelity of ribosome termination are not well understood.
Purpose of the Study:
- To investigate ribosome pausing at stop codons in mammalian cells.
- To understand the mechanisms and implications of termination pausing.
Main Methods:
- Developed a profiling strategy to capture terminating ribosomes.
- Utilized massively parallel reporter assays to validate findings.
- Analyzed sequence motifs and rRNA interactions.
Main Results:
- Identified heterogeneity in ribosome pausing at individual stop codons.
- Discovered an upstream sequence motif that promotes termination pausing.
- Found that reduced pausing increases stop codon slippage and C-terminal protein heterogeneity.
- Observed tissue-specific pausing patterns linked to Rps26 stoichiometry.
Conclusions:
- Termination pausing is a regulated process influenced by mRNA sequence and ribosome composition.
- Pausing affects translational fidelity and generates protein diversity.
- Cell-specific regulation of termination pausing exists.
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