Meiotic drivers are genetic elements that break Mendel's law of segregation to be transmitted into more than half of the offspring produced by a heterozygote. The success of a driver relies on outcrossing (mating between individuals from distinct lineages) because drivers gain their advantage in heterozygotes. It is, therefore, curious that Schizosaccharomyces pombe, a species reported to rarely outcross, harbors many meiotic drivers. To address this paradox, we measured mating phenotypes in S. pombe natural isolates. We found that the propensity for cells from distinct clonal lineages to mate varies between natural isolates and can be affected both by cell density and by the available sexual partners. Additionally, we found that the observed levels of preferential mating between cells from the same clonal lineage can slow, but not prevent, the spread of a wtf meiotic driver in the absence of additional fitness costs linked to the driver. These analyses reveal parameters critical to understanding the evolution of S. pombe and help explain the success of meiotic drivers in this species.
Original data underlying this manuscript can be accessed from the Stowers Original Data Repository at http://www.stowers.org/research/publications/libpbxxxx.Base called reads are available as fastq files at the SRA under project accession number PRJNA732453.
Diverse mating phenotypes impact the spread of wtf meiotic drivers in Schizosaccharomyces pombeNCBI Sequence Read Archive, PRJNA732453.
Mate-pair sequencing of S. kambucha lab strain SZY661SRA SRX4224586.
- Sarah E Zanders
- Sarah E Zanders
- Sarah E Zanders
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Tatiana Giraud, Université Paris-Sud, France
© 2021, López Hernández 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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