Related Experiment Video
Updated: Jun 5, 2025
04:04
Real-Time Quantification of the Effects of IS200/IS605 Family-Associated TnpB on Transposon Activity
Published on: January 20, 2023
2.3K
Transposable element exonization generates a reservoir of evolving and functional protein isoforms
Yago A Arribas1, Blandine Baudon1, Maxime Rotival2
1Institut Curie, PSL University, Inserm U932, Immunity and Cancer, 75005 Paris, France.
Cell
|December 12, 2024
Summary
Transposable elements (TEs) can be spliced into new protein isoforms, adding to human proteome diversity. These functional, albeit lowly expressed, TE-spliced isoforms are conserved across individuals and may be shaped by natural selection.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- Alternative splicing generates protein diversity, including via exonization of transposable elements (TEs).
- The biological relevance and proteomic contribution of unannotated TE-spliced transcripts remain largely unknown.
Purpose of the Study:
- To characterize a population of unannotated TE-exonizing isoforms generated by mRNA splicing.
- To investigate their prevalence, translation efficiency, and functional relevance in human populations.
Main Methods:
- Transcriptome assembly
- Ribosome profiling
- Proteomics
- Functional analyses
Main Results:
- Identified 1,227 unannotated TE-exonizing isoforms, recurrent in human populations.
- These isoforms are efficiently translated, stably expressed, and exhibit specific cellular localization, sometimes with modified functions.
- Exonized TEs are often ancient, associated with recent splice sites, and contribute to isoform secondary structure.
Conclusions:
- TE-spliced isoforms represent a significant reservoir of functional protein diversity.
- These isoforms are subject to natural selection, highlighting their evolutionary importance.
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