Abstract：
To identify odors in complex environments accurately, insects have evolved multiple olfactory proteins. In our study, various olfactory proteins of Odontothrips loti Haliday, an oligophagous pest that primarily affects Medicago sativa (alfalfa), were explored. Specifically, 47 putative olfactory candidate genes were identified in the antennae transcriptome of O. loti, including seven odorant-binding proteins (OBPs), nine chemosensory proteins (CSPs), seven sensory neuron membrane proteins (SNMPs), eight odorant receptors (ORs), and sixteen ionotropic receptors (IRs). PCR analysis further confirmed that 43 out of 47 genes existed in O. loti adults, and O.lotOBP1, O.lotOBP4, and O.lotOBP6 were specifically expressed in the antennae with a male-biased expression pattern. In addition, both the fluorescence competitive binding assay and molecular docking showed that p-Menth-8-en-2-one, a component of the volatiles of the host, had strong binding ability to the O.lotOBP6 protein. Behavioral experiments showed that this component has a significant attraction to both female and male adults, indicating that O.lotOBP6 plays a role in host location. Furthermore, molecular docking reveals potential active sites in O.lotOBP6 that interact with most of the tested volatiles. Our results provide insights into the mechanism of O. loti odor-evoked behavior and the development of a highly specific and sustainable approach for thrip management.
摘要：
为了准确识别复杂环境中的气味，昆虫已经进化出多种嗅觉蛋白。在我们的研究中,各种嗅觉蛋白OdontothripslotiHaliday，一种主要影响紫花苜蓿（苜蓿）的寡食害虫，被探索。具体来说,在O.loti的触角转录组中鉴定出47个推定的嗅觉候选基因，包括七种气味结合蛋白（OBP），九种化学感觉蛋白（CSP），七种感觉神经元膜蛋白（SNMPs），八种气味受体（ORs），和十六个离子型受体（IRs）。PCR分析进一步证实，47个基因中有43个存在于O.loti成虫中，和O.lotOBP1，O.lotOBP4和O.lotOBP6在触角中以男性偏向的表达模式特异性表达。此外,荧光竞争结合实验和分子对接实验均显示p-Menth-8-en-2-one,宿主挥发物的成分，对O.lotOBP6蛋白有很强的结合能力。行为实验表明，该成分对成年女性和男性都有显著的吸引力，指示O.lotOBP6在主机位置中发挥作用。此外，分子对接揭示了O.lotOBP6中与大多数测试挥发物相互作用的潜在活性位点。我们的结果提供了对O.loti气味诱发行为的机制的见解，并开发了高度特异性和可持续的thrip管理方法。
