Guerrero F D, Davey R B, Miller R J
Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS, Kerrville, TX 78028, USA.
J Med Entomol. 2001 Jan;38(1):44-50. doi: 10.1603/0022-2585-38.1.44.
A polymerase chain reaction-based assay was developed to detect the presence of a pyrethroid resistance-associated amino acid substitution in Boophilus microplus (Canestrini). The assay uses a simple method for the extraction of genomic DNA from individual larvae and genotypes individuals for the presence of a Phe-->Ile amino acid substitution in the S6 transmembrane segment of domain III of the para-like sodium channel, clearly distinguishing heterozygotes from homozygotes. High frequencies for this amino acid substitution were found in the Corrales and San Felipe strains, which have target site insensitivity mechanisms for pyrethroid resistance. The Caporal resistant strain contained lower yet substantial numbers of amino acid-substituted alleles. Low amino acid substitution frequencies were found in the susceptible reference Gonzales strain and the Coatzacoalcos strain, which has metabolic esterase-mediated pyrethroid resistance. The amino acid substitution was not found in six other strains that were susceptible to pyrethroids.
已开发出一种基于聚合酶链反应的检测方法，用于检测微小牛蜱（Canestrini）中与拟除虫菊酯抗性相关的氨基酸替代的存在情况。该检测方法采用一种简单的方法从单个幼虫中提取基因组DNA，并对个体进行基因分型，以检测类para钠通道结构域III的S6跨膜片段中是否存在苯丙氨酸（Phe）向异亮氨酸（Ile）的氨基酸替代，能够清晰地区分杂合子和纯合子。在科拉莱斯和圣费利佩菌株中发现该氨基酸替代的频率较高，这两种菌株具有拟除虫菊酯抗性的靶标位点不敏感机制。卡波拉尔抗性菌株中氨基酸替代等位基因的数量较少但仍相当可观。在敏感的参考菌株冈萨雷斯菌株以及具有代谢酯酶介导的拟除虫菊酯抗性的科阿特萨科科斯菌株中，氨基酸替代频率较低。在对拟除虫菊酯敏感的其他六个菌株中未发现该氨基酸替代。
