Ontogenetic stage-specific quantitative trait loci contribute to divergence in developmental trajectories of sexually dimorphic fins between medaka populations
Ontogenetic stage-specific quantitative trait loci contribute to divergence in developmental trajectories of sexually dimorphic fins between medaka populations
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个体发育阶段特异性数量性状基因座导致青鳉种群之间性二态性鳍发育轨迹的差异
DOI：
10.1111/mec.12933
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发表时间：
2014
影响因子：
4.9
通讯作者：
Jun Kitano
中科院分区：
文献类型：
--
作者：
Maiko Kawajiri;Kohta Yoshida;Shingo Fujimoto;Daniel Frikli Mokodongan;Mark Ravinet;Mark Kirkpatrick;Kazunori Yamahira;Jun Kitano
当雄性和雌性的最适表型不同时，性别二型性就会进化。然而，遗传限制可能会限制性别二型性的进化。一种可能的制约来自两性表达的等位基因。由于男性和女性的大部分基因组都是相同的，所以不同性别之间具有不同适合度的共享等位基因面临着局部性冲突。另一个潜在的制约因素是发育阶段之间的遗传相关性。在成年阶段，性二形性状往往是受欢迎的，但在幼年时期则是相反的，因此个体发育阶段之间的性状发展脱钩对于成年性二型性的进化可能是必要的。因此，解决性别和年龄之间的灶内冲突是性别二型性的年龄特异性表达进化的关键。我们研究了两个群体间性别二态个体发育分化的遗传结构，这两个群体在臀部和背鳍长度上的二态程度不同。数量性状基因座(QTL)定位表明，很少有QTL在整个个体发育阶段具有一致的效应，大多数QTL改变个体发育过程中影响鳍生长速率的大小和方向。我们还发现，大多数QTL是性别特异的，这表明局灶性冲突几乎得到了解决。我们的结果表明，性别和年龄特定的QTL使种群能够在复杂的自然选择和性别选择中实现性别二态特征的最佳发展轨迹。
Sexual dimorphism can evolve when males and females differ in phenotypic optima. Genetic constraints can, however, limit the evolution of sexual dimorphism. One possible constraint is derived from alleles expressed in both sexes. Because males and females share most of their genome, shared alleles with different fitness effects between sexes are faced with intralocus sexual conflict. Another potential constraint is derived from genetic correlations between developmental stages. Sexually dimorphic traits are often favoured at adult stages, but selected against as juvenile, so developmental decoupling of traits between ontogenetic stages may be necessary for the evolution of sexual dimorphism in adults. Resolving intralocus conflicts between sexes and ages is therefore a key to the evolution of age‐specific expression of sexual dimorphism. We investigated the genetic architecture of divergence in the ontogeny of sexual dimorphism between two populations of the Japanese medaka (Oryzias latipes) that differ in the magnitude of dimorphism in anal and dorsal fin length. Quantitative trait loci (QTL) mapping revealed that few QTL had consistent effects throughout ontogenetic stages and the majority of QTL change the sizes and directions of effects on fin growth rates during ontogeny. We also found that most QTL were sex‐specific, suggesting that intralocus sexual conflict is almost resolved. Our results indicate that sex‐ and age‐specific QTL enable the populations to achieve optimal developmental trajectories of sexually dimorphic traits in response to complex natural and sexual selection.