GEM-DMC2 Unit, The CABD (CSIC-UPO-JA), Ctra. de Utrera km 1, 41013, Seville, Spain.
Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia and Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain.
Nat Commun. 2020 May 26;11(1):2631. doi: 10.1038/s41467-020-16284-8.
The evolution of winged insects revolutionized terrestrial ecosystems and led to the largest animal radiation on Earth. However, we still have an incomplete picture of the genomic changes that underlay this diversification. Mayflies, as one of the sister groups of all other winged insects, are key to understanding this radiation. Here, we describe the genome of the mayfly Cloeon dipterum and its gene expression throughout its aquatic and aerial life cycle and specific organs. We discover an expansion of odorant-binding-protein genes, some expressed specifically in breathing gills of aquatic nymphs, suggesting a novel sensory role for this organ. In contrast, flying adults use an enlarged opsin set in a sexually dimorphic manner, with some expressed only in males. Finally, we identify a set of wing-associated genes deeply conserved in the pterygote insects and find transcriptomic similarities between gills and wings, suggesting a common genetic program. Globally, this comprehensive genomic and transcriptomic study uncovers the genetic basis of key evolutionary adaptations in mayflies and winged insects.
有翅昆虫的进化彻底改变了陆地生态系统，并导致了地球上最大的动物辐射。然而，我们仍然不完全了解支持这种多样化的基因组变化。蜉蝣作为所有其他有翅昆虫的姐妹群之一，是理解这种辐射的关键。在这里，我们描述了蜉蝣 Cloeon dipterum 的基因组及其在水生和空中生命周期及其特定器官中的基因表达。我们发现气味结合蛋白基因的扩张，其中一些在水生若虫的呼吸鳃中特异性表达，表明该器官具有新的感觉作用。相比之下，飞行的成虫以性二态的方式使用扩大的视蛋白组，其中一些仅在雄性中表达。最后，我们确定了一组在翼类昆虫中深度保守的翅膀相关基因，并发现鳃和翅膀之间的转录组相似性，表明存在共同的遗传程序。总的来说，这项全面的基因组和转录组研究揭示了蜉蝣和有翅昆虫关键进化适应的遗传基础。
