An amino acid substitution attributable to insecticide-insensitivity of acetylcholinesterase in a Japanese encephalitis vector mosquito, Culex tritaeniorhynchus
An amino acid substitution attributable to insecticide-insensitivity of acetylcholinesterase in a Japanese encephalitis vector mosquito, Culex tritaeniorhynchus
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DOI：
10.1016/j.bbrc.2003.11.141
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发表时间：
2004-01-16
影响因子：
3.1
通讯作者：
Tomita, T
中科院分区：
文献类型：
--
作者：
Nabeshima, T;Mori, A;Tomita, T
三带喙库蚊乙酰胆碱酯酶（AChE）前体701个氨基酸残基的cDNA序列被鉴定为AChE基因（Ace2）的第二个转录物。Ace2基因与2号染色体上的有机磷杀虫剂（OP）不敏感密切相关。比较了一株杀虫剂敏感菌株和抗性菌株TYM之间的cDNA序列，发现TYM对乙酰胆碱酯苯醚的敏感性降低了870倍。在TYM蚊中存在两个氨基酸替换。一个是F455W，其在Torped AChE （Phe331）中的同源位置位于活性位点峡谷酰基袋中的催化His附近。另一个取代位于c端Ile697位置，该位置显然被排除在成熟蛋白之外，与催化活性无关。乙酰胆碱酯酶2基因的F455W替换是导致TYM蚊对乙酰胆碱酯酶不敏感的唯一原因。(C) 2003 Elsevier Inc.版权所有。
A cDNA sequence encoding a Drosophila Ace-paralogous acetylcholinesterase (AChE) precursor of 701 amino acid residues was identified as the second AChE gene (Ace2) transcript from Culex tritaeniorhynchus. The Ace2 gene is tightly linked to organophosphorus insecticide (OP)-insensitivity of AChE on chromosome 2. The cDNA sequences were compared between an insecticide-susceptible strain and the resistant strain, TYM, that exhibits a 870-fold decrease in fenitroxon-sensitivity of AChE. Two amino acid substitutions were present in TYM mosquitoes. One is F455W whose homologous position in Torped AChE (Phe331) is located in the vicinity of the catalytic His in the acyl pocket of the active site gorge. The other substitution is located to a C-terminal Ile697 position that apparently seems to be excluded from the mature protein and is irrelevant to catalytic activity. The F455W replacement in the Ace2 gene is solely responsible for the insecticide-insensitivity of AChE in TYM mosquitoes. (C) 2003 Elsevier Inc. All rights reserved.