The effect of hybridization on transposable element accumulation in an undomesticated fungal species
- Université Laval, Canada
Abstract
Transposable elements (TEs) are mobile genetic elements that can profoundly impact the evolution of genomes and species. A long-standing hypothesis suggests that hybridization could deregulate TEs and trigger their accumulation, although it received mixed support from studies in plants and animals. Here, we tested this hypothesis in fungi using incipient species of the undomesticated yeast Saccharomyces paradoxus. Population genomic data revealed no signature of higher transposition in natural hybrids. As we could not rule out the elimination of past transposition increase signatures by natural selection, we performed a laboratory evolution experiment on a panel of artificial hybrids to measure TE accumulation in the near absence of selection. Changes in TE copy numbers were not predicted by the level of evolutionary divergence between the parents of a hybrid genotype. Rather, they were highly dependent on the individual hybrid genotypes, showing that strong genotype-specific deterministic factors govern TE accumulation in yeast hybrids.
Data availability
Illumina short read sequencing data of the MA lines is available at NCBI under accession PRJNA515073. Genome assemblies and Nanopore long read sequencing data of wild isloates are available at NCBI under accession PRJNA514804. Illumina short read sequencing data of wild isolates is available at NCBI under accessions PRJNA277692, PRJNA324830 and PRJNA479851.
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Ploidy instability in experimental hybrid populationsNCBI BioProject, PRJNA515073.
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Saccharomyces paradoxus Raw sequence readsNCBI BioProject, PRJNA324830.
Article and author information
Author details
Christian R Landry
Funding
Natural Sciences and Engineering Research Council of Canada (RGPIN-2015-03755)
- Christian R Landry
Natural Sciences and Engineering Research Council of Canada (NSERC Alexander Graham-Bell doctoral scholarship)
- Mathieu Hénault
- Guillaume Charron
Fonds de recherche du Québec – Nature et technologies (FRQNT doctoral scholarship)
- Mathieu Hénault
- Guillaume Charron
Fonds de Recherche du Québec - Santé (FRQS postdoctoral scholarship)
- Souhir Marsit
Canada Research Chairs (Canada Research Chair in Evolutionary Cell and Systems Biology)
- Christian R Landry
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Hénault et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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