Pervasive gene flow despite strong and varied reproductive barriers in swordtails.
Pervasive gene flow despite strong and varied reproductive barriers in swordtails.
复制标题
尽管剑尾鱼存在强大且多样的生殖障碍，但基因流动却很普遍。
DOI：
10.1101/2024.04.16.589374
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发表时间：
2024
期刊：
影响因子：
--
通讯作者：
Schumer,Molly
中科院分区：
文献类型：
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作者：
Aguillon,StepfanieM;HaaseCox,SophiaK;Langdon,QuinnK;Gunn,TheresaR;Baczenas,JohnJ;Banerjee,ShreyaM;Donny,AlexandraE;Moran,BenjaminM;Gutiérrez-Rodríguez,Carla;Ríos-Cárdenas,Oscar;Morris,MollyR;Powell,DanielL;Schumer,Molly
生殖障碍的进化导致了新物种的形成。然而，最近的研究表明，即使在强大的障碍存在的情况下，杂交也普遍存在于生命之树上。使用剑尾鱼(剑鱼属)，一种新兴的模式系统，我们通过结合来自自然杂交种群的基因组测序、实验实验室杂交、行为分析、精子测量和发育研究，记录了阻碍剑尾鱼和剑尾鱼之间基因流动的重叠机制。我们发现，在自然杂交种群中，分类交配在维持具有不同祖先的亚种群中起到了作用。使用F2杂交种，我们确定了几个强烈影响杂交种生存能力的基因组区域。值得注意的是，这些区域中的两个是导致X之间杂交的遗传不亲和性的原因。Birchmannius Malinche及其姊妹种--剑尾鸟。我们的结果表明，古老的杂交在这种共同的遗传不亲和性的起源中发挥了作用。此外，这些不相容区域的祖先不匹配对INX的表型和杂交存活有非常相似的后果。Cortezi×X.Birchmanni杂种为INX.Malinche×X.桦树杂交种。我们的发现确定了不同的生殖障碍，这些障碍塑造了自然杂交物种之间的遗传交换，并突出了杂交的复杂进化结果。
The evolution of reproductive barriers leads to the formation of new species. However, recent research has demonstrated that hybridization has been pervasive across the tree of life even in the presence of strong barriers. Using swordtail fishes (genusXiphophorus), an emerging model system, we document overlapping mechanisms that act as barriers to gene flow betweenXiphophorus birchmanniandXiphophorus corteziby combining genomic sequencing from natural hybrid populations, experimental laboratory crosses, behavioural assays, sperm measures and developmental studies. We show that assortative mating plays a role in maintaining subpopulations with distinct ancestry within natural hybrid populations. Using F2hybrids we identify several genomic regions that strongly impact hybrid viability. Strikingly, two of these regions underlie genetic incompatibilities in hybrids betweenX. birchmanniand its sister speciesXiphophorus malinche. Our results demonstrate that ancient hybridization has played a role in the origin of this shared genetic incompatibility. Moreover, ancestry mismatch at these incompatible regions has remarkably similar consequences for phenotypes and hybrid survival inX. cortezi×X. birchmannihybrids as inX. malinche×X. birchmannihybrids. Our findings identify varied reproductive barriers that shape genetic exchange between naturally hybridizing species and highlight the complex evolutionary outcomes of hybridization.