State Key Laboratory of Crop Stress Biology in Arid Areas, College of Plant Protection, Northwest A & F University, Yangling, Shaanxi Province, China.
School of Agricultural Sciences, Jiangxi Agricultural University, Nanchang, China.
Insect Sci. 2024 Apr;31(2):417-434. doi: 10.1111/1744-7917.13246. Epub 2023 Jul 19.
Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the larvae. Because short neuropeptide F (sNPF) and its receptor sNPFR are involved in a diversity of physiological functions, especially in functions related to feeding in insects, it is a molecular target for pest control. Herein, an sNPF and 2 sNPFRs were identified and cloned from M. separata. Bioinformatics analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains, respectively. The sNPF and its receptor genes were distributed across larval periods and tissues, but 2 receptors had distinct expression patterns. The starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent re-feeding. RNA interference knockdown of sNPF, sNPFR1, and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight, but also led to decrease of glycogen and total lipid contents, and increase of trehalose compared with double-stranded green fluorescent protein injection. Furthermore, molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold; the results indicated that both receptors were presumably activated by the mature peptide sNPF-2. These results revealed that sNPF signaling played a considerably vital role in the feeding regulation of M. separata and represents a potential control target for this pest.
分离麦蛾是一种臭名昭著的植食性害虫，由于幼虫贪吃，对谷类作物构成严重威胁。由于短神经肽 F（sNPF）及其受体 sNPFR 参与多种生理功能，尤其是与昆虫摄食相关的功能，因此它是害虫防治的一个分子靶标。本研究从分离麦蛾中鉴定并克隆了一个 sNPF 和 2 个 sNPFRs。生物信息学分析表明，sNPF 和其受体分别具有高度保守的 RLRFamide C 末端和 7 个跨膜结构域。sNPF 和其受体基因在幼虫期和组织中分布，但 2 个受体具有不同的表达模式。饥饿诱导实验表明，在食物剥夺下 sNPF 和 sNPFR 的表达水平下调，随后再喂养时恢复。通过将双链 RNA 注射到幼虫中干扰 sNPF、sNPFR1 和 sNPFR2 的 RNA 干扰，不仅抑制了食物的摄取，而且还导致了体型和体重的增加，同时降低了糖原和总脂质的含量，增加了海藻糖的含量，与双链绿色荧光蛋白注射相比。此外，还基于由 AlphaFold 构建的 3 维模型，对 sNPFR 蛋白与其配体 sNPF 之间的相互作用模式进行了分子对接；结果表明，这两个受体可能都被成熟肽 sNPF-2 激活。这些结果表明，sNPF 信号在分离麦蛾的摄食调节中起着至关重要的作用，代表了该害虫的一个潜在控制靶标。
