Provincial Key Laboratory for Botanical Pesticide R&D of Shaanxi Province, Yangling, Shaanxi 712100, PR China; Institute of Pesticide Science, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
Key Laboratory of Crop Pest Integrated Management on the Loess Plateau, Ministry of Agriculture, Yangling, Shaanxi 712100, PR China.
Pestic Biochem Physiol. 2018 Jun;148:190-198. doi: 10.1016/j.pestbp.2018.04.014. Epub 2018 Apr 27.
Pyrethroid insecticides modify the gating of voltage-gated sodium channels, thus disrupting the function of the nervous system. In Drosophila melanogaster, para encodes a functional sodium channel. Drosophila Sodium Channel 1 (DSC1), although considered as a putative sodium channel gene for decades due to its high sequence similarity with sodium channels, encodes a voltage-gated cation channel with high permeability to Ca. Previous study showed that knockout of the DSC1 gene (DSC1) caused Drosophila adults to be more susceptible to pyrethroids and the adult giant fiber (GF) neural circuit were more susceptible to pyrethroids. Considering distinct expression of DSC1 transcripts in adults and larvae, we examined the role of DSC1 channels in regulating pyrethroid susceptibility in Drosophila larvae. We conducted insecticide bioassays and examined the susceptibility of the larval neuromuscular junction (NMJ) to pyrethroids using w, an insecticide-susceptible line, DSC1, para (a pyrethroid-resistant line carrying a mutation in para) and a double mutation line para; DSC1. We found that, like the adult GF system, the NMJ of DSC1 flies is more susceptible to pyrethroids than that of w with the pyrethroid susceptibility ranked as DSC1 > w > para; DSC1 > para. However, DSC1 larvae were about two-fold more resistant to pyrethroids than w larvae, and the pyrethroid susceptibility of larvae ranked as w > DSC1 > para; DSC1 > para. These results reveal common and distinct roles of DSC1 channels in regulating the action of pyrethroids in adults and larvae of D. melanogaster.
拟除虫菊酯杀虫剂会改变电压门控钠离子通道的门控，从而破坏神经系统的功能。在黑腹果蝇中，para 编码一种功能性钠离子通道。尽管 Drosophila Sodium Channel 1（DSC1）由于与钠离子通道具有高度相似性，被认为是一种潜在的钠离子通道基因，但它编码的是一种对 Ca 具有高通透性的电压门控阳离子通道。先前的研究表明，DSC1 基因（DSC1）敲除会使果蝇成虫对拟除虫菊酯更为敏感，并且成虫巨大纤维（GF）神经回路对拟除虫菊酯更为敏感。考虑到 DSC1 转录本在成虫和幼虫中存在明显的表达差异，我们研究了 DSC1 通道在调节果蝇幼虫对拟除虫菊酯敏感性中的作用。我们进行了杀虫剂生物测定，并使用 w（一种对杀虫剂敏感的品系）、DSC1、para（一种带有 para 突变的对杀虫剂具有抗性的品系）和双突变品系 para; DSC1 来检测幼虫神经肌肉接头（NMJ）对拟除虫菊酯的敏感性。结果发现，与成年 GF 系统一样，DSC1 果蝇的 NMJ 比 w 对拟除虫菊酯更为敏感，其对拟除虫菊酯的敏感性排序为 DSC1＞w＞para; DSC1＞para。然而，DSC1 幼虫对拟除虫菊酯的抗性比 w 幼虫高约两倍，幼虫对拟除虫菊酯的敏感性排序为 w＞DSC1＞para; DSC1＞para。这些结果揭示了 DSC1 通道在调节黑腹果蝇成虫和幼虫中拟除虫菊酯作用方面的共同和不同作用。
