Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Pest Manag Sci. 2024 Aug;80(8):4055-4068. doi: 10.1002/ps.8112. Epub 2024 Apr 12.
The important wood-boring pest Batocera horsfieldi has evolved a sensitive olfactory system to locate host plants. Odorant-binding proteins (OBPs) are thought to play key roles in olfactory recognition. Therefore, exploring the physiological function of OBPs could facilitate a better understanding of insect chemical communications.
In this research, 36 BhorOBPs genes were identified via transcriptome sequencing of adults' antennae from B. horsfieldi, and most BhorOBPs were predominantly expressed in chemosensory body parts. Through fluorescence competitive binding and fluorescence quenching assays, the antenna-specific BhorOBP28 was investigated and displayed strong binding affinities forming stable complexes with five volatiles, including (+)-α-Pinene, (+)-Limonene, β-Pinene, (-)-Limonene, and (+)-Longifolene, which could also elicit conformation changes when they were interacting with BhorOBP28. Batocera horsfieldi females exhibited a preference for (-)-Limonene, and a repellent response to (+)-Longifolene. Feeding dsOBP19 produced by a bacteria-expressed system with a newly constructed vector could lead to the knockdown of BhorOBP28, and could further impair B. horsfieldi attraction to (-)-Limonene and repellent activity of (+)-Longifolene. The analysis of site-directed mutagenesis revealed that Leu7, Leu72, and Phe121 play a vital role in selectively binding properties of BhorOBP28.
By modeling the molecular mechanism of olfactory recognition, these results demonstrate that BhorOBP28 is involved in the chemoreception of B. horsfieldi. The bacterial-expressed dsRNA delivery system gains new insights into potential population management strategies. Through the olfactory process concluded that discovering novel behavioral regulation and environmentally friendly control options for B. horsfieldi in the future. © 2024 Society of Chemical Industry.
重要的钻蛀性害虫松墨天牛已经进化出了一种敏感的嗅觉系统来定位宿主植物。气味结合蛋白（OBP）被认为在嗅觉识别中起着关键作用。因此，探索 OBPs 的生理功能可以帮助我们更好地理解昆虫的化学通讯。
本研究通过松墨天牛成虫触角转录组测序，鉴定出 36 个 BhorOBPs 基因，其中大多数 BhorOBPs 主要在化学感受体部位表达。通过荧光竞争结合和荧光猝灭实验，对触角特异性 BhorOBP28 进行了研究，发现它与五种挥发性物质（包括（+）-α-蒎烯、（+）-柠檬烯、β-蒎烯、（-）-柠檬烯和（+）-长叶烯）具有强烈的结合亲和力，形成稳定的复合物，并且当它们与 BhorOBP28 相互作用时，还能引起构象变化。松墨天牛雌虫对（-）-柠檬烯表现出偏好，对（+）-长叶烯表现出排斥反应。用新构建的载体表达系统表达的 dsOBP19 喂养后，可以导致 BhorOBP28 的敲低，进一步损害松墨天牛对（-）-柠檬烯的吸引力和（+）-长叶烯的驱避活性。定点突变分析表明，Leu7、Leu72 和 Phe121 在 BhorOBP28 的选择性结合特性中起着至关重要的作用。
通过模拟嗅觉识别的分子机制，这些结果表明 BhorOBP28 参与了松墨天牛的化学感受。细菌表达的 dsRNA 传递系统为潜在的种群管理策略提供了新的见解。通过嗅觉过程得出结论，未来可以为松墨天牛发现新的行为调控和环保控制选项。© 2024 化学工业协会。
