Theory predicts that sexual reproduction can either facilitate or restrain transposable element (TE) accumulation by providing TEs with a means of spreading to all individuals in a population, versus facilitating TE load reduction via purifying selection. By quantifying genomic TE loads over time in experimental sexual and asexual Saccharomyces cerevisiae populations, we provide direct evidence that TE loads decrease rapidly under asexual reproduction.. We show, using simulations, that this reduction may occus via evolution of TE activity, most likely via increased excision rates. Thus, sex is a major driver of genomic TE loads and at the root of the success of TEs.
Raw read data of the experiment is available at SRA (BioProject identifier PRJNA308843). All data processing and analyses scripts as well as the simulator together with explanations are available at https://github.com/KamilSJaron/reproductive_mode_TE_dynamics.
Sex speeds adaptation by altering the dynamics of molecular evolutionNCBI BioProject, PRJNA308843.
- Jens Bast
- Tanja Schwander
- Tanja Schwander
- Jens Bast
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Graham Coop, University of California, Davis, United States
© 2019, Bast 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.
The tooth shape of sharks and mice are regulated by a similar signaling center despite their teeth having very different geometries.
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