Department of Entomology, China Agricultural University, Beijing, 100193, China.
Technology Center of Qinhuangdao Customs District, Qinhuangdao, 066004, China.
Sci Rep. 2020 May 21;10(1):8400. doi: 10.1038/s41598-020-65242-3.
Two unique housefly strains, PSS and N-PRS (near-isogenic line with the PSS), were used to clarify the mechanisms associated with propoxur resistance in the housefly, Musca domestica. The propoxur-selected resistant (N-PRS) strain exhibited >1035-fold resistance to propoxur and 1.70-, 12.06-, 4.28-, 57.76-, and 57.54-fold cross-resistance to beta-cypermethrin, deltamethrin, bifenthrin, phoxim, and azamethiphos, respectively, compared to the susceptible (PSS) strain. We purified acetylcholinesterase (AChE) from the N-PRS and PSS strains using a procainamide affinity column and characterized the AChE. The sensitivity of AChE to propoxur based on the bimolecular rate constant (K) was approximately 100-fold higher in the PSS strain compared to the N-PRS strain. The cDNA encoding Mdace from both the N-PRS strain and the PSS strain were cloned and sequenced using RT-PCR. The cDNA was 2073 nucleotides long and encoded a protein of 691 amino acids. A total of four single nucleotide polymorphisms (SNPs), I162M, V260L, G342A, and F407Y, were present in the region of the active site of AChE from the N-PRS strain. The transcription level and DNA copy number of Mdace were significantly higher in the resistant strain than in the susceptible strain. These results indicated that mutations combined with the up-regulation of Mdace might be essential in the housefly resistance to propoxur.
两种独特的家蝇品系，PSS 和 N-PRS（与 PSS 近等基因系），被用于阐明与家蝇对丙溴磷抗性相关的机制，家蝇，Musca domestica。丙溴磷选择的抗性（N-PRS）菌株对丙溴磷表现出>1035 倍的抗性，对β-氯氰菊酯、溴氰菊酯、联苯菊酯、辛硫磷和唑磷的交叉抗性分别为 1.70、12.06、4.28、57.76 和 57.54 倍，与敏感（PSS）菌株相比。我们使用普鲁卡因酰胺亲和柱从 N-PRS 和 PSS 菌株中纯化乙酰胆碱酯酶（AChE），并对 AChE 进行了表征。N-PRS 菌株和 PSS 菌株的 AChE 对丙溴磷的敏感性基于双分子速率常数（K），约为 N-PRS 菌株的 100 倍。使用 RT-PCR 从 N-PRS 菌株和 PSS 菌株克隆和测序了编码 Mdace 的 cDNA。cDNA 长 2073 个核苷酸，编码 691 个氨基酸的蛋白质。在 N-PRS 菌株 AChE 活性部位的区域存在 4 个单核苷酸多态性（SNP），I162M、V260L、G342A 和 F407Y。抗性菌株中 Mdace 的转录水平和 DNA 拷贝数明显高于敏感菌株。这些结果表明，突变与 Mdace 的上调相结合可能是家蝇对丙溴磷抗性的关键。
