Na+/K+-ATPase resistance and cardenolide sequestration: basal adaptations to host plant toxins in the milkweed bugs (Hemiptera: Lygaeidae: Lygaeinae)
Na+/K+-ATPase resistance and cardenolide sequestration: basal adaptations to host plant toxins in the milkweed bugs (Hemiptera: Lygaeidae: Lygaeinae)
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DOI：
10.1098/rspb.2014.2346
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发表时间：
2015-04-22
影响因子：
4.7
通讯作者：
Petschenka, Georg
中科院分区：
文献类型：
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作者：
Bramer, Christiane;Dobler, Susanne;Petschenka, Georg
尽管毒素的封存是植食性昆虫对植物防御的常见共同进化反应，但所涉及的性状的宏观进化在很大程度上尚未得到解决。利用包含来自四大洲的物种的系统发育方法，我们分析了半翅目Lygaeinae亚科中隔离有毒强心内酯的能力，该亚科与产生强心内酯的夹竹桃科广泛相关。此外，我们还分析了其 Na+/K+-ATP 酶（卡烯内酯的分子靶标）的抗性。我们的数据表明，强心烯内酯封存和强心烯内酯抗性Na+/K+-ATP酶是Lygaeinae的基础适应。在转移到非夹竹桃科宿主的两个物种中，隔离能力继而降低，但 Na+/K+-ATP 酶抗性得以维持。我们认为，这两个特征是一起进化的，代表了导致莱格虫进化成功的主要共同进化适应。此外，对强心烯内酯的专门化并不是进化的死胡同，而是使这种昆虫谱系能够从远缘科中转移到产生强心粉内酯的植物。
Despite sequestration of toxins being a common coevolutionary response to plant defence in phytophagous insects, the macroevolution of the traits involved is largely unaddressed. Using a phylogenetic approach comprising species from four continents, we analysed the ability to sequester toxic cardenolides in the hemipteran subfamily Lygaeinae, which is widely associated with cardenolide-producing Apocynaceae. In addition, we analysed cardenolide resistance of their Na+/K+-ATPases, the molecular target of cardenolides. Our data indicate that cardenolide sequestration and cardenolide-resistant Na+/K+-ATPase are basal adaptations in the Lygaeinae. In two species that shifted to non-apocynaceous hosts, the ability to sequester was secondarily reduced, yet Na+/K+-ATPase resistance was maintained. We suggest that both traits evolved together and represent major coevolutionary adaptations responsible for the evolutionary success of lygaeine bugs. Moreover, specialization on cardenolides was not an evolutionary dead end, but enabled this insect lineage to host shift to cardenolide-producing plants from distantly related families.