Recombination shapes the diversification of the <i>wtf</i> meiotic drivers.

Abstract

Meiotic drivers are selfish genetic elements that distort fair segregation. The <i>wtf</i> genes are poison-antidote meiotic drivers that are experiencing rapid diversification in fission yeasts. However, gene duplication alone is insufficient to drive the diversification of <i>wtf</i> genes, given the poison encoded by a newly duplicated <i>wtf</i> gene can be detoxified by the antidote encoded by the original <i>wtf</i> gene. Here, we analyze the evolution of <i>wtf</i> genes across 21 strains of <i>Schizosaccharomyces pombe</i>. Knocking out each of 25 <i>wtf</i> genes in <i>S. pombe</i> strain 972h- separately does not attenuate the yeast growth, indicating that the <i>wtf</i> genes might be largely neutral to their carriers in asexual life cycle. Interestingly, <i>wtf</i> genes underwent recurrent and intricate recombination. As proof of principle, we generate a novel meiotic driver through artificial recombination between <i>wtf</i> drivers, and its encoded poison cannot be detoxified by the antidotes encoded by their parental <i>wtf</i> genes but can be detoxified by its own antidote. Therefore, we propose that recombination can generate new meiotic drivers and thus shape the diversification of the <i>wtf</i> drivers.