Haplotype independence contributes to evolvability in the long-term absence of sex in a mite

Oztoprak, H.; Gao, S.; Guiglielmoni, N.; Brandt, A.; Zheng, Y.; Becker, C.; Becker, K.; Bednarski, V.; Borgschulte, L.; Burak, K. A.; Dion-Cote, A.-M.; Leonov, V.; Opherden, L.; Shimano, S.; Bast, J.

doi:10.1101/2023.09.07.556471

bioRxiv · 10.1101/2023.09.07.556471

Haplotype independence contributes to evolvability in the long-term absence of sex in a mite

Oztoprak, H.·Gao, S.·Guiglielmoni, N.·Brandt, A.·Zheng, Y.·Becker, C.·Becker, K.·Bednarski, V.·Borgschulte, L.·Burak, K. A.·Dion-Cote, A.-M.·Leonov, V.·Opherden, L.·Shimano, S.·Bast, J.

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Abstract

Some unique asexual species persist over time and contradict the consensus that sex is a prerequisite for long-term evolutionary survival. How they escape the dead-end fate remains enigmatic. Here, we generated a haplotype-resolved genome assembly based on a single individual and collected genomic data from worldwide populations of the parthenogenetic diploid oribatid mite Platynothrus peltifer to identify signatures of persistence without sex. We found that haplotypes diverge independently since the transition to asexuality at least 20 my ago. Multiple lines of evidence indicate disparate evolutionary trajectories between haplotypic blocks. Our findings imply that such haplotypic independence can lead to non-canonical routes of evolvability, helping some species to adapt, diversify and persist for millions of years in the absence of sex. One-Sentence SummaryFunctionally different chromosome sets in an asexual mite species showcase a survival strategy spanning millions of years.

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Oztoprak, H., Gao, S., Guiglielmoni, N., Brandt, A., Zheng, Y., Becker, C., Becker, K., Bednarski, V., Borgschulte, L., Burak, K. A., Dion-Cote, A.-M., Leonov, V., Opherden, L., Shimano, S., Bast, J.. 2023-09-10. Haplotype independence contributes to evolvability in the long-term absence of sex in a mite. https://doi.org/10.1101/2023.09.07.556471

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