Proteomic Analysis On The Enhanced Fecundity Of Nilaparvata Lugens (St(?)l) Induced By Jinggangmycin And The Functional Study Of The Key Gene Fatty Acid Synthase

The brown planthopper (BPH), Nilaparvata lugens (Stal) (Hemiptera:Delphacidae), is a classic pest of rice crops whose resurgence is induced by pesticides. The antibiotic fungicide jinggangmycin (JGM) is mainly used in controlling the rice sheath blight, Rhizoctonia solani, which is commonly overused due to low toxicity, environmental residue and cost. Our related report documented both spray and topical application of JGM(JGM-S and JGM-T) enhanced reproduction of BPH, with the enhancement of JGM-S more obvious. To date, however, molecular mechanisms of the enhancement are unclear. Here, we screen out the key proteins by analyzing ovarian proteins of BPH females of different treatments in order to explore the molecular mechanisms and the reason for the more obvious enhancement of JGM-S.1. Proteomic analysis on the ovaries of BPH females following different treatment methods of JGMIsobaric tags for relative and absolute quantitation (iTRAQ) protocols were used to carry out proteomic analysis on the ovaries of BPH females following different treatment methods of JGM. We recorded changes in expression of 284 proteins (142(?) and 142(?)) in JGM-S compared to the JGM-S control group (S-control); 267 proteins were differentially expressed (130(?) and 137(?)) in JGM-T compared to the JGM-T control group (T-control); 114 proteins (62(?) and 52(?)) were differentially expressed in JGM-S compared to the JGM-T group. Based on pathway annotation and enrichment analysis, we chose fatty acid synthase(FAS) for further study which was more highly expressed in JGM-S vs S-control and JGM-S vs JGM-T groups.2. Influence on the reproduction of BPH after interfered with FASWe interfered the RNA of BPH by feeding method, forming JGM-S+dsFAS treatment (the expression of FAS in the JGM-S+dsFAS treatment decreased by 58% compared to JGM-S). The results of oviposition showed that suppressing FAS significantly influenced the number of eggs laid (decreasing by 46%), oviposition period (decreasing by 33%), and longevity of BPH females (decreasing by 24%). Suppressing FAS also decreased the contents of oleic acid, palmitic acid, linoleic acid, stearic acid, myristic acid in the ovary and oleic acid, palmitic acid, myristic acid in the fat body of BPH females.3. Changes of physiology and biochemistry after feeding BPH with JGM Feeding JGM(100ppm,20ppm) increased the expression of fatty acid synthase(54%, 56%) and vitellogenin(133%,94%) of BPH females compared to control. After feeding BPH females with JGM of 20ppm for further study, the content of soluble sugar increased by 46%; the content of insulin increased by 17%; the body weight increased by 10%; the number of symbiotic bacteria increased by 38%. Suppressing FAS significantly influenced the body weight, while had no influence on the number of symbiotic bacteria.