Tomihara Kenta, Pinharanda Ana, Kwon Young Mi, Taverner Andrew M, Kors Laura, Aardema Matthew L, Holder Julia C, Poyraz Lin, Reilly Patrick F, Kiuchi Takashi, Andolfatto Peter
Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, University of Tokyo; Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan.
Department of Biological Sciences, Columbia University; 1212 Amsterdam Avenue, New York, NY, 10027, USA.
bioRxiv. 2025 Aug 12:2025.08.10.669386. doi: 10.1101/2025.08.10.669386.
Closely related species often exhibit distinct morphologies that can contribute to species-specific adaptations and reproductive isolation. One example are Lepidopteran caterpillar appendages, such as the "caudal horn" of Bombycoidea moths, which have evolved substantial morphological diversity among species in this group. Using interspecific crosses, we identify the genetic basis of the caudal horn size difference between and its closest relative . One major QTL contributes more than 10% to the mean horn length difference between the two species. This QTL encompasses a conserved -family gene cluster, key upstream regulators that are well-known for their roles in morphological diversification in animals. Using allele-specific expression analysis and CRISPR/Cas9 knockouts, we show that cis-regulatory changes to and contribute to the species difference in caudal horn size. This kind of modularity enables highly pleiotropic genes, including key upstream growth regulators, to contribute to the evolution of morphological traits without causing widespread deleterious effects.
亲缘关系密切的物种通常表现出独特的形态，这些形态有助于物种特异性适应和生殖隔离。一个例子是鳞翅目毛虫的附肢，比如蚕蛾科蛾类的“尾角”，在该类群的物种间已经进化出了显著的形态多样性。通过种间杂交，我们确定了[物种名称1]与其最亲近的[物种名称2]之间尾角大小差异的遗传基础。一个主要的数量性状位点（QTL）对这两个物种之间平均角长差异的贡献率超过10%。这个QTL包含一个保守的[基因家族名称]基因簇，以及关键的上游调控因子，这些上游调控因子因其在动物形态多样化中的作用而广为人知。通过等位基因特异性表达分析和CRISPR/Cas9基因敲除，我们表明[基因名称1]和[基因名称2]的顺式调控变化导致了尾角大小的物种差异。这种模块化使得包括关键上游生长调控因子在内的高度多效性基因能够促进形态特征的进化，而不会造成广泛的有害影响。
