Guo Juxin, Xu Yang, Yang Xiaoshan, Sun Xiaohong, Sun Yan, Zhou Dan, Ma Lei, Shen Bo, Zhu Changliang
Department of Pathogen Biology, Nanjing Medical University, Nanjing, China.
Department of Microbiology, Shanxi Medical University Jinci College, Taiyuan, China.
Arch Insect Biochem Physiol. 2019 Apr;100(4):e21538. doi: 10.1002/arch.21538. Epub 2019 Feb 19.
Cuticular resistance, characterized by decreased epidermal penetration, has been reported on highly pyrethroid-resistant mosquitoes. In this study, we examined the role of genes in the chitin biosynthetic pathway in the context of deltamethrin-resistant (DR) Culex pipiens pallens. We found that expression of the trehalase (TRE1) gene and chitin synthase (CHS1) gene was upregulated 1.65- and 1.75-fold with quantitative reverse transcription polymerase chain reaction, respectively, in the DR strain as compared with the deltamethrin-susceptible (DS) strain. Examination of chitin content in DR and DS pupae showed an increased amount of chitin in DR pupae. To further establish the role of TRE1 and CHS1 in deltamethrin resistance, we injected mosquitoes with small interfering RNA (siRNA) for knockdown of TRE1 or CHS1 expression. The mortality rates of DR mosquitoes exposed to insecticides increased 17% and 26% after siTRE1 and siCHS1 injection, respectively. The siRNA treatment against TRE1 resulted in decreased expression of the downstream gene CHS1. Together, our findings support a role of TRE1 and CHS1 in the regulation of pyrethroid resistance.
在对拟除虫菊酯具有高度抗性的蚊子中，已报道了以表皮穿透性降低为特征的表皮抗性。在本研究中，我们在对溴氰菊酯具有抗性（DR）的淡色库蚊背景下，研究了几丁质生物合成途径中基因的作用。我们发现，与对溴氰菊酯敏感（DS）的品系相比，在DR品系中，通过定量逆转录聚合酶链反应，海藻糖酶（TRE1）基因和几丁质合酶（CHS1）基因的表达分别上调了1.65倍和1.75倍。对DR和DS蛹中的几丁质含量进行检测发现，DR蛹中的几丁质含量增加。为了进一步确定TRE1和CHS1在溴氰菊酯抗性中的作用，我们向蚊子注射小干扰RNA（siRNA）以敲低TRE1或CHS1的表达。注射siTRE1和siCHS1后，接触杀虫剂的DR蚊子的死亡率分别提高了17%和26%。针对TRE1的siRNA处理导致下游基因CHS1的表达降低。我们的研究结果共同支持了TRE1和CHS1在拟除虫菊酯抗性调节中的作用。
