Larval transcriptomes reflect the evolutionary history of plant-insect associations

Over many decades we have observed that the potential host repertoire of a phytophagous caterpillar is different than the plant repertoire chosen by their butterfly mother for oviposition. These observations have been done particularly in species within the Nymphalidae family of butteflies. The discrepancy between life stages in terms of host range provides a possible explanation for the appearance of a polyphagous taxon within a clade of specialists taxa, as we have also observed in our phylogenetic analysis. We tested whether there is a \"transcriptional\" memory inspecting gene expression in the gut of different species of caterpillars in the Nymphalini tribe of butterflies exhibiting discrepancies of host range between life stages.

数十年来，学界已观察到植食性毛虫的潜在寄主谱与其亲代蝶类雌虫为产卵所选择的寄主植物谱并不一致。此类研究观察尤其针对蛱蝶科（Nymphalidae）的物种展开。寄主谱在不同生活史阶段的差异，可为专食性类群支系内出现多食性类群提供一种潜在解释，这一推论也在我们的系统发育分析中得到了佐证。我们针对蛱蝶族（Nymphalini）内存在生活史阶段寄主谱差异的多种蝶类毛虫，通过检测其肠道内的基因表达情况，验证了是否存在‘转录记忆（transcriptional memory）’这一现象。