Xu Wenping, Liu Songlin, Zhang Yang, Gao Jufang, Yang Mingjun, Liu Xiao, Tao Liming
Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.
College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China.
Pestic Biochem Physiol. 2017 Oct;142:77-82. doi: 10.1016/j.pestbp.2017.01.008. Epub 2017 Jan 7.
In order to elucidate the molecular mechanisms of cypermethrin resistance in Culex pipiens pallens Coq, the susceptible strain (SS strain) and cypermethrin resistant strain (CR strain) of Cx. p. pallens were investigated in this paper. The cypermethrin resistance ratio of CR strain to SS strain was measured by biological assays method, the cDNA sequence of sodium channel was cloned and analyzed. Real-time quantitative RT-PCR was used to detect the expression levels of the detoxification-related genes across between CR strain and SS strain of Cx. p. pallens. Bioassays indicated that CR strain was 283.06 and 80.68-fold resistance to cypermethrin and permethrin as compared to the susceptible strain, respectively. The sequence variability analysis of sodium channel gene between SS strain and CR strain shows that 4 point mutations (R954Q, L1023F, S1775G and A1989E) appear on the amino acid sequence of sodium channel of CR strain. The transcriptional levels of CYP6Z10, CYP9M10, CPGSTd1 and CPGSTd2 in the resistant strain are significantly higher than it is in the susceptible. The transcripts of CYP4H34 and E4 esterase have no significant difference between the CR strain and SS strain. The results indicated that sodium channel mutations, combined with elevated levels of P450s and GSTs, are associated with cypermethrin resistance in CR strain.
为阐明淡色库蚊对氯氰菊酯抗性的分子机制，本文对淡色库蚊敏感品系（SS品系）和氯氰菊酯抗性品系（CR品系）进行了研究。采用生物测定法测定CR品系对SS品系的氯氰菊酯抗性比值，克隆并分析钠通道的cDNA序列。运用实时定量RT-PCR检测淡色库蚊CR品系和SS品系中解毒相关基因的表达水平。生物测定表明，与敏感品系相比，CR品系对氯氰菊酯和氯菊酯的抗性分别为283.06倍和80.68倍。SS品系和CR品系钠通道基因的序列变异分析显示，CR品系钠通道氨基酸序列上出现4个点突变（R954Q、L1023F、S1775G和A1989E）。抗性品系中CYP6Z10、CYP9M10、CPGSTd1和CPGSTd2的转录水平显著高于敏感品系。CR品系和SS品系之间CYP4H34和E4酯酶的转录本无显著差异。结果表明，钠通道突变以及P450s和GSTs水平升高与CR品系对氯氰菊酯的抗性有关。
