Related Experiment Video
Updated: Sep 30, 2025
09:13
In vivo Interrogation of Central Nervous System Translatome by Polyribosome Fractionation
Published on: April 30, 2014
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The interplay between translational efficiency, poly(A) tails, microRNAs, and neuronal activation
Timothy J Eisen1,2, Jingyi Jessica Li3, David P Bartel1,2
1Howard Hughes Medical Institute, Cambridge, Massachusetts 02142, USA.
RNA (New York, N.Y.)
|March 11, 2022
Summary
Translational efficiency (TE) in neurons is minimally impacted by poly(A)-tail length and microRNAs. Codon composition and mRNA folding energy are key drivers of TE, offering insights into neuronal gene regulation.
Area of Science:
- Neuroscience
- Molecular Biology
- Genetics
Background:
- Post-transcriptional control is crucial for neuronal function.
- Translational efficiency (TE) regulates gene expression in neurons.
Purpose of the Study:
- Investigate mRNA features influencing TE in neurons.
- Examine the roles of poly(A)-tail length, microRNAs, and neuronal activation in TE.
- Determine factors driving translational control in neuronal cells.
Main Methods:
- Analysis of translational efficiency (TE) in neuronal and brain tissues.
- Correlation studies between TE, poly(A)-tail length, and microRNA activity.
- Computational modeling to identify mRNA features affecting TE, including codon composition and folding energy.
Main Results:
- Poly(A)-tail length has a modest correlation with TE (<5% variance), with minimal impact.
- MicroRNAs primarily affect mRNA levels, not TE or tail length.
- Codon composition and mRNA folding energy are significant correlates of TE, explaining 38%-45% of variance.
- Neuronal activation induces cytoplasmic polyadenylation in a subset of mRNAs.
Conclusions:
- Translational control in bulk neuronal cells resembles that of other cell types.
- Factors beyond poly(A)-tail length and microRNAs, such as codon usage and mRNA structure, are critical for TE.
- Further research distinguishing translation in neuronal processes versus cell bodies may reveal specialized control mechanisms.
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