烟碱型乙酰胆碱受体（nAChRs）α6亚基变异剪接产生截短的无功能蛋白，是西花蓟马等多种重要害虫对多杀菌素产生抗性的主要原因，但其调控机制不明。本项目拟以多杀菌素敏感和抗性西花蓟马近等基因系为试虫，克隆敏感和抗性品系nAChR α6亚基基因组DNA，找出突变位点、变异剪接信号及调控作用元件等，利用Minigene技术研究变异转录本与DNA序列变异的关系；基于转录组测序数据，研究选择性剪接相关剪接蛋白以及调控反式作用因子蛋白基因序列及表达谱的种群差异，采用RNAi研究其在变异剪接体形成中的作用；研究完整型及变异转录本的电生理反应，用RNAi进行功能分析。研究结果一方面能够阐明多杀菌素抗性西花蓟马nAChR α6亚基变异转录本的形成及调控机制，为抗性治理提供依据；另一方面可以明确不同转录本的功能及与抗性的关系，揭示多杀菌素类药剂高抗性风险的机制，为以nAChRs为靶标杀虫剂的研发提供理论依据。

Nicotinic acetylcholine receptors (nAChRs) are neurotransmitter-gated ion channels that play a vital role in nerve signaling at the postsynaptic membrane of both vertebrates and invertebrates. The alternations of nAChR α6 subunit that result in truncated nonfunctional proteins is the major reason for spinosad resistance in many insect pests including Fankliniella occidentalis (Pergande). However, the regulation mechanisms for the mutated transcripts remain unclear. In order to clarify this, the near-isogenic lines of spinosad-susceptible (Ivf03) and -resistant (NIL-R) F. occidentalis will be used in the present project. Firstly, to clone the full genomic DNA of nAChR α6 subunit in both Ivf03 and NIL-R and then to find the stable mutation sites， altered splicing signals and regulation elements in DNA sequence. To examine the association of mutation in DNA and truncated transcripts by using Minegene technique. Secondly, based on the transcriptome sequence data to study the changes in sequence and expression of the alternative splicing related splicing proteins and trans-acting elements and then to investigate their roles in the formation of mutated transcripts by using RNAi technique. Finally, to evaluate the functions of full-length transcripts and mutated transcripts using RNAi and two-electrode voltage clamps. The results will elucidate the regulation mechanisms of the altered nAChR α6 subuint in spinosad resistant F. occidentalis and will provide basis for resistance management. Moreover, the results will clarify the relationship between the function of different transcripts and resistance, and will reveal the mechanisms of high risk of spinosad resistance, which will provide theoretical evidence for innovative insecticides targeting at nAChRs.