Zhu Jinghua, Zhu Kunmiao, Li Liang, Li Zengxin, Qin Weiwei, Park Yoonseong, He Yueping
Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Department of Entomology, Kansas State University, Manhattan, KS 66506, USA.
Insects. 2020 Sep 1;11(9):582. doi: 10.3390/insects11090582.
Honeydew is a watery fluid excreted by plant sap-feeding insects. It is a waste product for the insect hosts. However, it plays important roles for other organisms, such as serving as a nutritional source for beneficial insects and bacteria, as well as elicitors and effectors modulating plant responses. In this study, shotgun LC-MS/MS analyses were used to identify the proteins in the honeydew from two important rice hemipteran pests, the brown planthopper (, BPH) and green rice leafhopper (, GRH). A total of 277 and 210 proteins annotated to insect proteins were identified in the BPH and GRH honeydews, respectively. These included saliva proteins that may have similar functions as the saliva proteins, such as calcium-binding proteins and apolipophorin, involved in rice plant defenses. Additionally, a total of 52 and 32 proteins were identified in the BPH and GRH honeydews, respectively, some of which are involved in the plant immune system, such as Pathogen-Related Protein 10, ascorbate peroxidase, thioredoxin and glutaredoxin. Coincidently, 570 and 494 bacteria proteins were identified from the BPH and GRH honeydews, respectively, which included several well-known proteins involved in the plant immune system: elongation factor Tu, flagellin, GroEL and cold-shock proteins. The results of our study indicate that the insect honeydew is a complex fluid cocktail that contains abundant proteins from insects, plants and microbes, which may be involved in the multitrophic interactions of plants-insects-microbes.
蜜露是吸食植物汁液的昆虫分泌的一种水性液体。它是昆虫宿主的一种废弃物。然而，它对其他生物体起着重要作用，例如作为有益昆虫和细菌的营养来源，以及调节植物反应的诱导物和效应物。在本研究中，采用鸟枪法液相色谱-串联质谱分析来鉴定两种重要的水稻半翅目害虫褐飞虱（BPH）和白背飞虱（GRH）蜜露中的蛋白质。在BPH和GRH蜜露中分别鉴定出总共277种和210种注释为昆虫蛋白质的蛋白质。这些蛋白质包括可能与唾液蛋白具有相似功能的蛋白质，如参与水稻植株防御的钙结合蛋白和载脂蛋白。此外，在BPH和GRH蜜露中分别鉴定出总共52种和32种蛋白质，其中一些参与植物免疫系统，如病程相关蛋白10、抗坏血酸过氧化物酶、硫氧还蛋白和谷氧还蛋白。巧合的是，从BPH和GRH蜜露中分别鉴定出570种和494种细菌蛋白质，其中包括几种参与植物免疫系统的著名蛋白质：延伸因子Tu、鞭毛蛋白、热休克蛋白60和冷休克蛋白。我们的研究结果表明，昆虫蜜露是一种复杂的混合液体，含有来自昆虫、植物和微生物的丰富蛋白质，可能参与植物-昆虫-微生物的多营养相互作用。
