BACKGROUND Venom is one of the most important sources of regulation factors used by parasitic Hymenoptera to redirect host physiology in favour of the developing offspring. This has stimulated a number of studies, both at functional and "omics" level, which, however, are still quite limited for ectophagous parasitoids that permanently paralyze and suppress their victims (i.e., idiobiont parasitoids). RESULTS Here we present a combined transcriptomic and proteomic study of the venom of the generalist idiobiont wasp Bracon nigricans, an ectophagous larval parasitoid of different lepidopteran species, for which we recently described the host regulation strategy and the functional role of the venom in the induction of physiological changes in parasitized hosts. The experimental approach used led to the identification of the main components of B. nigricans venom involved in host regulation. Enzymes degrading lipids, proteins and carbohydrates are likely involved in the mobilization of storage nutrients from the fat body and may concurrently be responsible for the release of neurotoxic fatty acids inducing paralysis, and for the modulation of host immune responses. CONCLUSION The present work contributes to fill the gap of knowledge on venom composition in ectoparasitoid wasps, and, along with our previous physiological study on this species, provides the foundation on which to develop a functional model of host regulation, based both on physiological and molecular data. This paves the way towards a better understanding of parasitism evolution in the basal lineages of Hymenoptera and to the possible exploitation of venom as source of bioinsecticidal molecules.

中文翻译：

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外寄生蜂 Bracon nigricans 的毒液学。


背景技术毒液是寄生膜翅目用来改变宿主生理机能以有利于后代发育的调节因子的最重要来源之一。这刺激了功能和“组学”水平上的大量研究，然而，对于永久麻痹和抑制受害者的外食性寄生蜂（即独特的寄生蜂）而言，这些研究仍然相当有限。结果在这里，我们对普通特异黄蜂 Bracon nigricans 的毒液进行了转录组学和蛋白质组学的联合研究，这是一种不同鳞翅目物种的外食性幼虫寄生蜂，我们最近描述了其宿主调节策略以及毒液在诱导寄生宿主的生理变化。使用的实验方法确定了参与宿主调节的黑拟杆菌毒液的主要成分。降解脂质、蛋白质和碳水化合物的酶可能参与从脂肪体中调动储存营养物质，并可能同时负责释放神经毒性脂肪酸，诱导麻痹，并调节宿主免疫反应。结论 目前的工作有助于填补外寄生蜂毒液成分的知识空白，并且与我们之前对该物种的生理学研究一起，为开发基于生理学和分子学的宿主调节功能模型奠定了基础。数据。这为更好地了解膜翅目基础谱系的寄生进化以及可能利用毒液作为生物杀虫分子的来源铺平了道路。