The rise and fall of the ancient northern pike master sex determining gene
Abstract
The understanding of the evolution of variable sex determination mechanisms across taxa requires comparative studies among closely related species. Following the fate of a known master sex-determining gene, we traced the evolution of sex determination in an entire teleost order (Esociformes). We discovered that the northern pike (Esox lucius) master sex-determining gene originated from a 65 to 90 million-year-old gene duplication event and that it remained sex-linked on undifferentiated sex chromosomes for at least 56 million years in multiple species. We identified several independent species- or population-specific sex determination transitions, including a recent loss of a Y-chromosome. These findings highlight the diversity of evolutionary fates of master sex-determining genes and the importance of population demographic history in sex determination studies. We hypothesize that occasional sex reversals and genetic bottlenecks provide a non-adaptive explanation for sex determination transitions.
Data availability
All gene sequences, genomic, Pool-seq and RAD-Seq reads were deposited under the common project number PRJNA634624.
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Sex determination in the EsociformesGenBank, PRJNA634624.
Article and author information
Author details
Funding
Agence Nationale de la Recherche (ANR-13-ISV7-0005)
- Yann Guiguen
Deutsche Forschungsgemeinschaft
- Manfred Schartl
Agence Nationale de la Recherche (ANR-10-INBS-09)
- Laurent Journot
Agence Nationale de la Recherche (ANR-10-INBS-09)
- Celine Roques
National Institute of Health (R01GM085318)
- John H Postlethwait
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Molly Przeworski, Columbia University, United States
Version history
- Received: September 6, 2020
- Accepted: January 27, 2021
- Accepted Manuscript published: January 28, 2021 (version 1)
- Version of Record published: February 8, 2021 (version 2)
Copyright
© 2021, Pan 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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