A toxin-antidote selfish element increases fitness of its host
- Georgia Institute of Technology, United States
Abstract
Selfish genetic elements can promote their transmission at the expense of individual survival, creating conflict between the element and the rest of the genome. Recently, a large number of toxin-antidote (TA) post-segregation distorters have been identified in non-obligate outcrossing nematodes. Their origin and the evolutionary forces that keep them at intermediate population frequencies are poorly understood. Here, we study a TA element in C. elegans called zeel-1;peel-1. Two major haplotypes of this locus, with and without the selfish element, segregate in C. elegans. We evaluate the fitness consequences of the zeel-1;peel-1 element outside of its role in gene drive in non-outcrossing animals, and demonstrate that loss of the toxin peel-1 decreased fitness of hermaphrodites and resulted in reductions in fecundity and body size. These findings suggest a biological role for peel-1 beyond toxin lethality. This work demonstrates that a TA element can provide a fitness benefit to its hosts, either during their initial evolution or by being co-opted by the animals following their selfish spread. These findings guide our understanding on how TA elements can remain in a population where gene drive is minimized, helping resolve the mystery of prevalent TA elements in selfing animals.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for all figures . Simulation code is included in a github: https://github.com/lijiang-long/TA_modeling.
Article and author information
Author details
Funding
National Institutes of Health (GM139594)
- Patrick T McGrath
National Institutes of Health (GM119744)
- Annalise B Paaby
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Erik C Andersen, Northwestern University, United States
Version history
- Received: July 5, 2022
- Preprint posted: July 15, 2022 (view preprint)
- Accepted: October 23, 2023
- Accepted Manuscript published: October 24, 2023 (version 1)
- Version of Record published: November 7, 2023 (version 2)
Copyright
© 2023, Long 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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A toxin-antidote selfish element increases fitness of its host
eLife 12:e81640.
https://doi.org/10.7554/eLife.81640
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