中国农业科学 ›› 2026, Vol. 59 ›› Issue (18): 4007-4020.doi: 10.3864/j.issn.0578-1752.2026.18.005

• 专题:面向农业害虫精准防控的机制解析、技术优化与决策支撑 • 上一篇    下一篇

韭菜迟眼蕈蚊气味结合蛋白OBP11的配体结合能力及关键氨基酸分析

王覃丽1(), 谭顺阳1, 夏根1, 刘文庆2, 杨玉婷1(), 田丽霞2()   

  1. 1 长江大学农学院/农业农村部长江中游作物绿色高效生产重点实验室(部省共建)/涝渍灾害与湿地农业湖北省重点实验室, 湖北荆州 434025
    2 北京市农林科学院植物保护研究所, 北京 100097
  • 收稿日期:2025-12-29 接受日期:2026-02-08 出版日期:2026-09-16 发布日期:2026-09-20
  • 通信作者:
    杨玉婷,E-mail:
    田丽霞,E-mail:
  • 联系方式: 王覃丽,E-mail:13477866904@163.com。
  • 基金资助:
    国家自然科学基金青年项目(32102202)

Ligand Binding Property and Key Amino Acid Analysis of Odorant- Binding Protein OBP11 in Bradysia odoriphaga

WANG QinLi1(), TAN ShunYang1, XIA Gen1, LIU WenQing2, YANG YuTing1(), TIAN LiXia2()   

  1. 1 College of Agriculture, Yangtze University/Ministry of Agriculture and Rural Affairs Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River (Co-Construction by Ministry and Province)/Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, Jingzhou 434025, Hubei
    2 Institute of Plant Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097
  • Received:2025-12-29 Accepted:2026-02-08 Published:2026-09-16 Online:2026-09-20

摘要:

【目的】明确韭菜迟眼蕈蚊(Bradysia odoriphaga)成虫触角高表达的气味结合蛋白BodoOBP11的分子特征,解析其在寄主定位中的嗅觉功能。【方法】利用生物信息学工具分析BodoOBP11的基本特征和进化关系;使用实时荧光定量PCR技术分析BodoOBP11在韭菜迟眼蕈蚊不同发育阶段和组织中的表达模式;通过大肠杆菌原核表达、镍柱亲和层析纯化和重组肠激酶酶切获得BodoOBP11蛋白;以1-NPN为荧光探针利用荧光竞争结合试验分析该蛋白与寄主植物韭菜的22种挥发性化合物和1种假定的性信息素化合物的结合能力;通过蛋白质结构预测、分子对接和定点突变揭示BodoOBP11蛋白与配体化合物的关键结合位点。【结果】BodoOBP11开放阅读框全长426 bp,编码141个氨基酸残基,在其氨基端有一段20个氨基酸残基组成的信号肽,且序列中具有Classic-C OBP的典型特征,即6个保守的半胱氨酸残基;其成熟蛋白预测分子量为13.53 kDa,等电点为7.71。实时荧光定量PCR结果表明,在不同发育阶段中,BodoOBP11在雄成虫中表达量最高,其次为雌成虫和蛹期。在不同组织中,BodoOBP11在雌、雄成虫的触角中均呈现显著高表达,且在雄虫触角中的表达量最高。荧光竞争结合试验显示,BodoOBP11仅与二丙基三硫醚、2-十三烷酮、二丙基二硫、2-十一烷酮、异硫氰酸苯乙酯及α-紫罗酮6种挥发物具有结合能力,其中与二丙基三硫醚结合能力最强。蛋白质结构预测与分子对接结果显示,BodoOBP11与上述6种配体的结合主要通过氢键与疏水相互作用,其中Thr74残基与2-十三烷酮、2-十一烷酮和α-紫罗酮形成氢键,而Val76、Ile107、Leu127、Met131、Phe138和Phe140等残基则主要介导疏水相互作用。定点突变后的荧光竞争结合试验显示,Ile107、Phe138和Phe140残基分别被突变成丙氨酸(Ala)后均会显著降低BodoOBP11与上述6种配体的结合能力,表明其为关键的结合位点。【结论】BodoOBP11对二丙基三硫醚、2-十三烷酮、二丙基二硫等6种韭菜挥发物表现出较强的结合亲和力,Ile107、Phe138和Phe140残基是其结合上述配体的关键残基。研究结果揭示了韭菜迟眼蕈蚊成虫利用BodoOBP11识别寄主植物挥发物的分子机制,可为基于嗅觉干扰的绿色防控技术研发提供依据。

关键词: 韭菜迟眼蕈蚊, 气味结合蛋白, 荧光竞争结合, 分子对接, 定点突变

Abstract:

【Objective】The objective of this study is to elucidate the molecular characteristics of the odorant-binding protein BodoOBP11, which is highly expressed in the antennae of adult Bradysia odoriphaga, and to investigate its olfactory function in host localization.【Method】Bioinformatics tools were used to analyze the basic characteristics and evolutionary relationships of BodoOBP11. The spatio-temporal expression patterns of BodoOBP11 across different developmental stages and tissues were then assessed using quantitative real-time PCR (qPCR). The BodoOBP11 protein was obtained through prokaryotic expression in E. coli, purification via nickel affinity chromatography, and cleavage using recombinant enterokinase. Using fluorescence competitive binding assays with the fluorescent probe 1-NPN, the binding ability of the protein to 22 volatile compounds from the host plant (Chinese chives) and one putative sex pheromone compound was subsequently evaluated. Finally, protein structure prediction, molecular docking, and site-directed mutagenesis were employed to identify the key binding sites between BodoOBP11 and ligand compounds.【Result】BodoOBP11 has an open reading frame of 426 bp, encoding 141 amino acid residues, including an N-terminal signal peptide of 20 amino acids. It exhibits the typical features of the Classic-C OBP, characterized by six conserved cysteine residues. The predicted molecular weight of the mature protein is 13.53 kDa, with an isoelectric point of 7.71. qPCR analysis revealed distinct expression patterns of BodoOBP11. Across developmental stages, its expression was highest in male adults, followed by female adults and pupae. In different tissues, BodoOBP11 showed significant high expression in the antennae of both sexes, with the highest level detected in male antennae. Fluorescence competitive binding assays demonstrated that BodoOBP11 binds to six volatiles: dipropyl trisulfide, 2-tridecanone, dipropyl disulfide, 2-undecanone, phenethyl isothiocyanate, and α-ionone. The strongest binding affinity was observed for dipropyl trisulfide. Protein structure prediction and molecular docking indicated that BodoOBP11 binds to these six ligands primarily via hydrogen bonding and hydrophobic interactions. Specifically, Thr74 forms hydrogen bonds with 2-tridecanone, 2-undecanone, and α-ionone, while residues Val76, Ile107, Leu127, Met131, Phe138, and Phe140 mainly mediate hydrophobic interactions. Site-directed mutagenesis followed by fluorescence competitive binding assays revealed that mutations of Ile107, Phe138, and Phe140 to alanine significantly reduced the binding affinity of BodoOBP11 to all six ligands, indicating their critical roles in binding.【Conclusion】BodoOBP11 exhibits strong binding affinity to six volatile compounds from Chinese chive, including dipropyl trisulfide, 2-tridecanone, and dipropyl disulfide, etc. Furthermore, residues Ile107, Phe138, and Phe140 were identified as crucial sites for binding these ligands. These findings preliminarily reveal its molecular mechanism in mediating host plant volatile recognition by adult B. odoriphaga using BodoOBP11, offering a theoretical foundation for developing green control technologies based on olfactory interference.

Key words: Bradysia odoriphaga, odorant-binding protein (OBP), fluorescence competitive binding, molecular docking, site-directed mutagenesis