Jiangsu Key Laboratory of Sericultural and animal biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212100, China.
Jiangsu Key Laboratory of Sericultural and animal biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212100, China; Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, The Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212100, China.
Insect Biochem Mol Biol. 2024 Oct;173:104177. doi: 10.1016/j.ibmb.2024.104177. Epub 2024 Aug 20.
Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is the most destructive pest, causing severe damage to mulberry production in China's sericulture industry. The insecticide application in mulberry orchards poses a significant risk of poisoning to Bombyx mori. Shifting from insecticides to odor attractants is a beneficial alternative, but not much data is available on the olfactory system of G. pyloalis. We identified 114 chemosensory genes from the antennal transcriptome database of G. pyloalis, with 18 odorant-binding protein (OBP) and 17 chemosensory protein (CSP) genes significantly expressed in the antennae. Ligand-binding assays for two antennae-biased expressed general odorant-binding proteins (GOBPs) showed high binding affinities of GOBP1 to hexadecanal, β-ionone, and 2-ethylhexyl acrylate, while GOBP2 exhibited binding to 4-tert-octylphenol, benzyl benzoate, β-ionone, and farnesol. Computational simulations indicated that van der Waal forces predominantly contributed to the binding free energy in the binding processes of complexes. Among them, Phe12 of GOBP1 and Phe19 of GOBP2 were demonstrated to play crucial roles in their bindings to plant volatiles using site-directed mutagenesis experiments. Moreover, hexadecanal and β-ionone attracted G. pyloalis male moths in the behavioral assays, while none of the candidate plant volatiles significantly affected female moths. Our findings provide a comprehensive understanding of the molecular mechanisms underlying olfactory recognition in G. pyloalis, setting the groundwork for novel mulberry pests control strategies based on insect olfaction.
豆天蛾（鳞翅目：螟蛾科）是一种极具破坏性的害虫，对中国桑蚕业的桑树生产造成严重危害。在桑园使用杀虫剂对家蚕构成了极大的中毒风险。从杀虫剂转向气味引诱剂是一种有益的替代方法，但关于豆天蛾嗅觉系统的资料并不多。我们从豆天蛾触角转录组数据库中鉴定出 114 个化学感受基因，其中 18 个气味结合蛋白（OBP）和 17 个化学感受蛋白（CSP）基因在触角中显著表达。对两种触角偏表达的一般气味结合蛋白（GOBP）进行配体结合测定，结果表明 GOBP1 对十六醛、β-紫罗兰酮和 2-乙基己烯酸具有高亲和力，而 GOBP2 对 4-叔辛基苯酚、苯甲酸苄酯、β-紫罗兰酮和法呢醇具有结合活性。计算模拟表明，范德华力在结合过程中对结合自由能起主要作用。其中，GOBP1 的 Phe12 和 GOBP2 的 Phe19 被证明在它们与植物挥发物的结合中起关键作用，这是通过定点突变实验得出的。此外，十六醛和β-紫罗兰酮在行为测定中吸引了豆天蛾雄蛾，而候选植物挥发物均未对雌蛾产生显著影响。我们的研究结果为豆天蛾嗅觉识别的分子机制提供了全面的认识，为基于昆虫嗅觉的新型桑树害虫控制策略奠定了基础。
