【摘要】 昆虫化学感受蛋白(chemosensory proteins, CSPs)在结合及运输气味物质的过程中发挥着重要作用。本研究利用RT-PCR克隆了花椒窄吉丁(Agrilus zanthoxylumi)化学感受蛋白基因AzanCSP7(GenBank No. ON409462)并对其进行了序列分析，结果显示，AzanCSP7基因的CDS区长度为333 bp，编码110个氨基酸，有4个保守的半胱氨酸，符合化学感受蛋白的典型特征。系统发育树分析发现，花椒窄吉丁蛋白AzanCSP7和苹果小吉丁(A. mali) AmalCSP8紧密聚为一支，置信度100%。通过qPCR检测AzanCSP7在雌、雄成虫的头、胸、腹、足、翅的表达情况，结果显示，AzanCSP7在雄虫和雌虫中的表达量均是在头部最高，且在雌虫头部和足部的表达量极显著高于雄虫(P<0.01)。使用RaptorX构建AzanCSP7三维模型后，通过AutoDock Vina与46种寄主挥发物配体进行分子对接，结果显示，寄主挥发物与AzanCSP7有2个主要的结合位置，位置1：由α-2螺旋(Glu29～Asn37)以及α-5螺旋和α-6螺旋之间的无规则卷曲(Gln84～Lys98)形成的凹槽，位置2：由α-4螺旋(Arg60～Arg71)和α-6螺旋(Glu99～Ser108)形成的凹槽；1组链状配体(香叶醇,月桂烯, α-罗勒烯,乙酸芳樟酯和乙酸香叶酯)和5组环状配体(可巴烯,荜澄茄油烯; β-榄香烯,葎草烯;右旋大根香叶烯,萜品油烯;胡椒酮, 4-侧柏醇, β-蒎烯, α-侧柏烯, β-水芹烯;莰烯, 4-蒈烯,倍半水芹烯,柠檬烯和3-蒈烯)分别与蛋白AzanCSP7有相同的作用氨基酸残基；筛选出6种与AzanCSP7结合力较好的配体(可巴烯, β-石竹烯, β-榄香烯,右旋大根香叶烯,荜澄茄油烯和葎草烯)。研究结果表明，AzanCSP7与寄主挥发物有较好的亲和力，参与了识别寄主挥发物的过程。本研究为阐明AzanCSP7在嗅觉机制中的功能提供理论依据。更多还原

【Abstract】 Insect chemosensory proteins(CSPs) play an important role in the process of binding and transporting odorants. In this study, the gene AzanCSP7 of Agrilus zanthoxylumi was cloned by RT-PCR and its sequence was analyzed. The length of the CDS(GenBank No. ON409462) of AzanCSP7 gene was 333 bp,encoding 110 amino acids. There were 4 conserved cysteine which conformed to the typical characteristics of CSPs. The phylogenetic tree analysis showed that AzanCSP7 of A. zanthoxylumi and AmalCSP8 of A. mali were form a clade closely, with 100% confidence. q PCR was used to detect the expression of AzanCSP7 in the head, thorax, abdomen, feet and wings of male and female adults. The results showed that the expression of AzanCSP7 in both male and female adults were highest in the head, and the expression in the head and feet of female adults were extremely significantly higher than that in male adults(P<0.01). After using RaptorX to build the three-dimensional model of AzanCSP7, molecular docking was carried out with 46 host volatiles ligands through AutoDock Vina. The results showed that there were 2 main binding positions between host volatiles and AzanCSP7, position 1: groove formed by α-2 Helix(Glu29～Asn37) and random coil(Gln84～Lys98) between α-5 Helix and α-6 Helix, position 2: groove formed by α-4 Helix(Arg60～Arg71) andα-6 Helix(Glu99～Ser108). There is a group of chain ligands(Geraniol, Mergence, Linalyl acetate, Geranyl acetate) and 5 groups of cyclic ligands(α-copaene, Pipertone; β-elemene, α-caryophyllene; Gemmacrene D,Terpinolene; Pipertone, 4-thujanol, β-pinene,(-)-α-thujone, β-phellandrene; Camphene, 4-carene, β-sesquiphellandrene,(+)-dipentene, 3-carene) had the same functional amino acid residues with protein AzanCSP7, respectively. Six ligands with good binding ability to AzanCSP7(α-copaene, caryophyllene, β-elemene, gemmacrene D, α-cubebene, α-caryophyllene). The results showed that AzanCSP7 had good affinity with host volatiles and participated in the process of recognizing host volatiles. This study provides a theoretical basis for clarifying the function of AzanCSP7 in olfactory mechanism.更多还原