A nicotinic acetylcholine receptor transmembrane point mutation (G275E) associated with resistance to spinosad in Frankliniella occidentalis.
A nicotinic acetylcholine receptor transmembrane point mutation (G275E) associated with resistance to spinosad in Frankliniella occidentalis.
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DOI：
10.1111/jnc.12029
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发表时间：
2013-03
影响因子：
4.7
通讯作者：
Millar NS
中科院分区：
文献类型：
--
作者：
Puinean AM;Lansdell SJ;Collins T;Bielza P;Millar NS
西花蓟马是一种重要的蔬菜、水果和观赏作物害虫，此前已有报道表明西花蓟马对大环内酯类杀虫剂多杀菌素具有高度抗性。我们克隆了烟碱型乙酰胆碱受体α6亚基(Foα6)，并比较了敏感和抗多杀菌素昆虫种群(MLFOM和R1S)的α6核苷酸序列。Foα6基因发生单核苷酸突变，导致敏感昆虫中的甘氨酸(G)残基被抗性昆虫中的谷氨酸(E)取代。耐药相关突变(G275E)被预测位于Foα6的第三个α-螺旋跨膜区的顶端。虽然没有直接证据确定多杀菌素结合位点的位置，但线虫谷氨酸门控氯离子通道中的类似氨基酸位于另一种大环内酯农药伊维菌素的已知结合位点附近(4.4o)。耐药性相关突变的功能后果已经在人类nAChRα7亚单位中进行了检测。在α7中引入类似的(A272E)突变可以消除多杀菌素的调节作用，同时对乙酰胆碱的激活没有显著影响，这与多杀菌素具有变构作用机制是一致的。
High levels of resistance to spinosad, a macrocyclic lactone insecticide, have been reported previously in western flower thrips, Frankliniella occidentalis, an economically important insect pest of vegetables, fruit and ornamental crops. We have cloned the nicotinic acetylcholine receptor (nAChR) α6 subunit from F. occidentalis (Foα6) and compared the nucleotide sequence of Foα6 from susceptible and spinosad-resistant insect populations (MLFOM and R1S respectively). A single nucleotide change has been identified in Foα6, resulting in the replacement of a glycine (G) residue in susceptible insects with a glutamic acid (E) in resistant insects. The resistance-associated mutation (G275E) is predicted to lie at the top of the third α-helical transmembrane domain of Foα6. Although there is no direct evidence identifying the location of the spinosad binding site, the analogous amino acid in the C. elegans glutamate-gated chloride channel lies in close proximity (4.4 Å) to the known binding site of ivermectin, another macrocyclic lactone pesticide. The functional consequences of the resistance-associated mutation have been examined in the human nAChR α7 subunit. Introduction of an analogous (A272E) mutation in α7 abolishes the modulatory effects of spinosad whilst having no significant effect upon activation by acetylcholine, consistent with spinosad having an allosteric mechanism of action.
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影响因子：
4.1
作者：
Bielza, Pablo
通讯作者：
Bielza, Pablo
影响因子：
3.6
作者：
Amiri, Shiva;Shimomura, Masaru;Sattelle, David B.
通讯作者：
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影响因子：
4.7
作者：
Lansdell, Stuart J.;Collins, Toby;Millar, Neil S.
通讯作者：
Millar, Neil S.
影响因子：
4.8
作者：
Lynagh, Timothy;Webb, Timothy I.;Lynch, Joseph W.
通讯作者：
Lynch, Joseph W.
影响因子：
4.7
作者：
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通讯作者：
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