Sun L, Wang Q, Yang S, Wang Q, Zhang Z, Khashaveh A, Zhang Y-J, Guo Y-Y
Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
Insect Mol Biol. 2017 Oct;26(5):601-615. doi: 10.1111/imb.12322. Epub 2017 Jun 20.
The polyphagous mirid bug Adelphocoris lineolatus relies heavily on olfactory cues to track suitable host plants. Thus, a better understanding of the molecular basis of its olfactory detection could contribute to the development of effective pest management strategies. In the present study, we report the expression profile of the odorant binding protein gene A. lineolatus odorant binding protein 6 (AlinOBP6). Quantitative real-time PCR experiments suggest that AlinOBP6 is female adult antennae-biased. Cellular immunolocalization analyses show that AlinOBP6 is highly expressed in the lymph of both multiporous sensilla basiconica and uniporous sensilla chaetica. A ligand binding analysis showed that recombinant AlinOBP6 not only bound tightly to host plant volatile compounds but also to nonvolatile compounds. Homology modelling and molecular docking analyses confirmed these unusual ligand binding profiles and revealed that the amino acid residues involved in the recognition of volatile and nonvolatile compounds are distinct. The results of our study are the first to suggest that an antenna- and female-biased OBP in an hemipteran insect is expressed in both olfactory and gustatory sensilla as a mechanism to respond to volatile and nonvolatile host compounds. These findings warrant further research into the molecular mechanisms of chemosensation for mirid bugs in responsive to host plant location.
多食性盲蝽 Adelphocoris lineolatus 严重依赖嗅觉线索来追踪适宜的寄主植物。因此，深入了解其嗅觉检测的分子基础有助于制定有效的害虫管理策略。在本研究中，我们报告了气味结合蛋白基因——牧草盲蝽气味结合蛋白6（AlinOBP6）的表达谱。实时定量PCR实验表明，AlinOBP6在雌性成虫触角中表达偏向性较高。细胞免疫定位分析表明，AlinOBP6在多孔锥形感器和单孔毛形感器的淋巴液中均高度表达。配体结合分析表明，重组AlinOBP6不仅与寄主植物挥发性化合物紧密结合，还与非挥发性化合物结合。同源建模和分子对接分析证实了这些不同寻常的配体结合模式，并揭示了参与识别挥发性和非挥发性化合物的氨基酸残基是不同的。我们的研究结果首次表明，半翅目昆虫中一种在触角和雌性中表达偏向性较高的OBP在嗅觉和味觉感器中均有表达，作为对挥发性和非挥发性寄主化合物作出反应的一种机制。这些发现值得进一步研究牧草盲蝽对寄主植物定位作出反应的化学感受分子机制。
