甜菜夜蛾尿苷二磷酸糖基转移酶对毒死蜱敏感性的影响  

The effects of UDP-glycosyltransferases on chlorpyrifos susceptibility to Spodoptera exigua

作　　者：黄河 胡波 胡松竹 钮建国 魏琪 薛圆 苏建亚 HUANG He;HU Bo;HU Songzhu;NIU Jianguo;WEI Qi;XUE Yuan;SU Jianya(College of Plant Protection/Key Laboratory of Integrated Management of Crop Disease and Pests,Ministry of Education,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学植物保护学院/农作物生物灾害综合治理教育部重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2019年第3期448-455,共8页Journal of Nanjing Agricultural University

基　　金：国家自然科学基金项目(31272063)

摘　　要：[目的]尿苷二磷酸(UDP)糖基转移酶(UGT)是生物体内广泛分布的Ⅱ相解毒代谢酶,目前有关昆虫体内UGT与杀虫剂解毒代谢及抗药性关系的研究还很少。本研究旨在探究甜菜夜蛾对毒死蜱敏感性与UGT基因表达的关系。[方法]采用叶片浸渍法测定甜菜夜蛾对毒死蜱的抗性水平;用定量PCR分析抗性与敏感种群间UGT基因表达水平的差异;以α-萘酚为底物、尿苷二磷酸葡萄糖为糖供体测定UGT活性,并测定UGT抑制剂对杀虫剂毒力的影响。[结果]采自广东惠州田间的种群对毒死蜱具有高达944.3倍的抗药性,所测定的32个UGT基因在抗性种群中有17个显著上调表达,其中以UGT33J3、UGT33F7、UGT33F5上调最明显,分别上调41、37与34倍,并且田间种群UGT活性是敏感种群的3倍。UGT基因的表达与UGT活性能被苯巴比妥与毒死蜱处理所诱导而增加,UGT活性的提高使甜菜夜蛾的敏感性下降。反过来使用UGT抑制剂5-硝基脲嘧啶与苯磺唑酮则能抑制甜菜夜蛾幼虫UGT的活性,并显著提高杀虫剂对甜菜夜蛾的毒力。[结论]甜菜夜蛾UGT对毒死蜱的代谢起着重要的作用,抑制UGT活性可提高甜菜夜蛾对杀虫剂的敏感性,说明UGT是甜菜夜蛾重要的杀虫剂解毒酶系。[Objectives]UDP-glycosyltransferases(UGT)are phaseⅡdetoxification enzymes widely distributed within living organisms.However,the roles of insect UGT in insecticide detoxification are less understood.This study tries to analyze the relationship between chlorpyrifos susceptibility and UGT expression in Spodoptera exigua.[Methods]Leaf dipping method was applied to assay the resistance level of S.exigua larvae,and the gene expression levels in susceptible and resistant populations were determined by RT-qPCR.The UGT enzymatic activities were measured usingα-naphthol as substrate and UDP-glucose as sugar donate.The effects of UGT inhibitors on chlorpyrifos toxicity were also assayed.[Results]Bioassay indicated S.exigua collected from Huizhou,Guangdong Province had developed very high resistance to chlorpyrifos,and the resistance ratio was 944.3-fold compared with the susceptible population.17 of 32 UGT genes were found to be over-expressed in the field population,among which UGT33J3,UGT33F7,UGT33F5 were the most up-regulated expressed,with 41,37 and 34-fold over-expression in field population,respectively.This field population also had significantly higher UGT activity than the susceptible one(3-fold).The expression of UGT genes could be induced by phenobarbital and chlorpyrifos challenges,and the UGT activities were also increased by such challenges.The increased UGT activity conferred by induced expression of UGT genes decreased the toxicity of chlorpyrifos on larvae of S.exigua.Reversely,the application of UGT inhibitors(5-nitropyrimidine and sulfopyridine)enhanced the toxicity of this insecticide on S.exigua larvae.[Conclusions]These data represent that the UGT of S.exigua play an important role in chlorpyrifos metabolism,and the inhibitions of UGT activity enhance the susceptibility of S.exigua to insecticide,suggesting that UGT is the important detoxification enzymes.

关 键 词：尿苷二磷酸糖基转移酶 甜菜夜蛾 毒死蜱 敏感性 解毒代谢 

分 类 号：Q965.9[生物学—昆虫学]