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Transposable elements maintain genome-wide heterozygosity in inbred populations
Hanne De Kort1, Sylvain Legrand2, Olivier Honnay3
1Plant Conservation and Population Biology, University of Leuven, Kasteelpark Arenberg 31-2435, BE-3001, Leuven, Belgium. hanne.dekort@kuleuven.be.
Nature Communications
|November 17, 2022
Summary
Transposable elements (TEs) may help inbred species persist by maintaining genetic diversity. This study in Arabidopsis lyrata reveals TEs boost variation in functional genes, supporting the success of self-fertilizing organisms.
Area of Science:
- Genomics
- Evolutionary Biology
- Plant Science
Background:
- Inbreeding increases extinction risk but many inbred species thrive.
- Transposable elements (TEs) are mobile genetic sequences.
- Understanding genetic variation maintenance under inbreeding is crucial.
Purpose of the Study:
- To investigate the role of transposable elements (TEs) in maintaining genetic variation.
- To explore how TEs influence evolutionary potential in inbred species.
- To examine genome-wide heterozygosity and selection signatures near TEs in Arabidopsis lyrata.
Main Methods:
- Analysis of genome-wide heterozygosity across an inbreeding gradient in Arabidopsis lyrata.
- Identification of single nucleotide polymorphisms (SNPs) near transposable elements (TEs).
- Assessment of selection signatures associated with TEs and stress-responsive genes.
Main Results:
- Elevated heterozygosity downstream of TE superfamilies under intense inbreeding.
- Signatures of balancing selection linked to TEs.
- Increased heterozygosity in stress-responsive genes located near TEs.
- Reproducible TE-associated selection signatures across independent lineages.
Conclusions:
- Transposable elements (TEs) can maintain genetic variation in functional genomic regions.
- TEs may provide a mechanism for the evolutionary success of inbreeding species.
- This study offers a novel hypothesis for the adaptability of self-fertilizing organisms.
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