Schweizer Fabian, Heidel-Fischer Hanna, Vogel Heiko, Reymond Philippe
Department of Plant Molecular Biology, University of Lausanne, 1015 Lausanne, Switzerland.
Department of Entomology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
Insect Biochem Mol Biol. 2017 Jun;85:21-31. doi: 10.1016/j.ibmb.2017.04.004. Epub 2017 Apr 26.
Phytophagous insects have to deal with toxic defense compounds from their host plants. Although it is known that insects have evolved genes and mechanisms to detoxify plant allochemicals, how specialist and generalist precisely respond to specific secondary metabolites at the molecular level is less understood. Here we studied the larval performance and transcriptome of the generalist moth Heliothis virescens and the specialist butterfly Pieris brassicae feeding on Arabidopsis thaliana genotypes with different glucosinolate (GS) levels. H. virescens larvae gained significantly more weight on the GS-deficient mutant quadGS compared to wild-type (Col-0) plants. On the contrary, P. brassicae was unaffected by the presence of GS and performed equally well on both genotypes. Strikingly, there was a considerable differential gene expression in H. virescens larvae feeding on Col-0 compared to quadGS. In contrast, compared to H. virescens, P. brassicae displayed a much-reduced transcriptional activation when fed on both plant genotypes. Transcripts coding for putative detoxification enzymes were significantly upregulated in H. virescens, along with digestive enzymes and transposable elements. These data provide an unprecedented view on transcriptional changes that are specifically activated by GS and illustrate differential molecular responses that are linked to adaptation to diet in lepidopteran herbivores.
植食性昆虫必须应对来自其寄主植物的有毒防御化合物。尽管已知昆虫已经进化出基因和机制来解毒植物次生代谢物，但专食性和广食性昆虫在分子水平上如何精确响应特定的次生代谢物却鲜为人知。在这里，我们研究了以不同芥子油苷（GS）水平的拟南芥基因型为食的广食性蛾类烟草天蛾和专食性蝴蝶粉纹夜蛾的幼虫表现和转录组。与野生型（Col-0）植株相比，烟草天蛾幼虫在缺乏GS的突变体quadGS上体重增加显著更多。相反，粉纹夜蛾不受GS存在的影响，在两种基因型上的表现同样良好。引人注目的是，与quadGS相比，取食Col-0的烟草天蛾幼虫存在相当大的基因表达差异。相比之下，与烟草天蛾相比，粉纹夜蛾在取食两种植物基因型时转录激活程度大大降低。在烟草天蛾中，编码假定解毒酶的转录本以及消化酶和转座元件显著上调。这些数据提供了关于由GS特异性激活的转录变化的前所未有的观点，并说明了与鳞翅目食草动物对食物适应相关的差异分子反应。
