The Cyprinodon variegatus genome reveals gene expression changes underlying differences in skull morphology among closely related species

Background: Understanding the genetic and developmental origins of phenotypic novelty is central to the study of biological diversity. In this study we identify modifications to the expression of genes at four developmental stages that may underlie jaw morphological differences among three closely related species of pupfish (genus Cyprinodon) from San Salvador Island, Bahamas. Pupfishes on San Salvador Island are trophically differentiated and include two endemic species that have evolved jaw morphologies unlike that of any other species in the genus Cyprinodon. Results: We find that gene expression differs significantly across recently diverged species of pupfish. Genes such as Bmp4 and calmodulin, previously implicated in jaw diversification in African cichlid fishes and Galapagos finches, were not found to be differentially expressed among species of pupfish. Instead we find multiple growth factors and cytokine/chemokine genes to be differentially expressed among these pupfish tax...背景：解析表型新颖性的遗传与发育起源，是生物多样性研究的核心议题。本研究针对采自巴哈马圣萨尔瓦多岛的3种近缘鲤齿鳉（Cyprinodon属），对其4个发育阶段的基因表达修饰模式进行了鉴定，这些修饰或为该类群颌部形态差异的潜在分子基础。圣萨尔瓦多岛的鳉鱼存在营养生态位分化，其中包含2种特有物种，它们演化出的颌部形态与鲤齿鳉属内其余所有物种均存在显著差异。 结果：研究结果显示，近缘分化的鳉鱼物种间基因表达存在显著差异。此前被证实参与非洲慈鲷与加拉帕戈斯地雀颌部形态多样化过程的骨形态发生蛋白4（Bmp4）与钙调蛋白（calmodulin），在本研究的鳉鱼物种间未呈现差异表达。与之相反，本研究发现多种生长因子及细胞因子/趋化因子基因在这些鳉鱼类群间存在差异表达……