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Updated: May 21, 2026
10:56
Polysome Fractionation and Analysis of Mammalian Translatomes on a Genome-wide Scale
Published on: May 17, 2014
Widespread uncoupling between transcriptome and translatome variations after a stimulus in mammalian cells
Toma Tebaldi1, Angela Re, Gabriella Viero
1Laboratory of Translational Genomics, Centre for Integrative Biology, University of Trento, 38123 Trento, Italy.
BMC Genomics
|June 8, 2012
Summary
Gene expression regulation is more complex than previously thought. This study reveals that changes in mRNA levels (transcriptome) and their translation (translatome) are largely independent, suggesting novel regulatory mechanisms.
Area of Science:
- Molecular Biology
- Genomics
- Cell Biology
Background:
- The classical model of eukaryotic gene expression assumes mRNA levels dictate translation availability.
- This study investigates the relationship between total mRNA (transcriptome) and polysome-associated mRNA (translatome) following stimuli.
Purpose of the Study:
- To investigate the relationship between transcriptome and translatome dynamics.
- To determine if mRNA abundance changes correlate with translational activity.
Main Methods:
- Simultaneous profiling of total and polysome-associated mRNAs using microarrays.
- Analysis of 20 transcriptome/translatome comparisons in mammalian cells under various conditions.
Main Results:
- EGF pathway activation shows early transcriptome and translatome changes, but 90% of variation is translatome-specific.
- Less than 5% of changes are concordant between transcriptome and translatome.
- Extensive uncoupling between RNA levels and translational activity is a general rule.
- Genes related to translation show a strong tendency for translational-level control.
- Statistical analysis demonstrates a lack of dependence between transcriptome and translatome changes.
Conclusions:
- A model of "diffused independency" between transcript abundance and polysome engagement is proposed.
- This suggests specific, yet unidentified, mechanisms couple transcriptional and translational regulation.
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