Laboratory of Agrozoology, Department of Crop Protection, Faculty of Agricultural and Applied, Biological Sciences, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Insect Biochem Mol Biol. 2012 Jul;42(7):455-65. doi: 10.1016/j.ibmb.2012.03.002. Epub 2012 Mar 21.
The cys-loop ligand-gated ion channel (cysLGIC) super family of Tetranychus urticae, the two-spotted spider mite, represents the largest arthropod cysLGIC super family described to date and the first characterised one within the group of chelicerates. Genome annotation, phylogenetic analysis and comparison of the cysLGIC subunits with their counterparts in insects reveals that the T. urticae genome encodes for a high number of glutamate- and histamine-gated chloride channel genes (GluCl and HisCl) compared to insects. Three orthologues of the insect γ-aminobutyric acid (GABA)-gated chloride channel gene Rdl were detected. Other cysLGIC groups, such as the nAChR subunits, are more conserved and have clear insect orthologues. Members of cysLGIC family mediate endogenous chemical neurotransmission and they are prime targets of insecticides. Implications for toxicology associated with the identity and specific features of T. urticae family members are discussed. We further reveal the accumulation of known and novel mutations in different GluCl channel subunits (Tu_GluCl1 and Tu_GluCl3) associated with abamectin resistance in T. urticae, and provide genetic evidence for their causality. Our study provides useful toxicological insights for the exploration of the T. urticae cysLGIC subunits as putative molecular targets for current and future chemical control strategies.
二斑叶螨 cys 环配体门控离子通道（cysLGIC）超家族代表了迄今为止描述的最大节肢动物 cysLGIC 超家族，也是螯肢动物组中第一个被描述的 cysLGIC 超家族。通过对 cysLGIC 亚基进行基因组注释、系统发育分析和与昆虫对应物的比较，发现与昆虫相比，二斑叶螨基因组编码了大量的谷氨酸门控氯通道基因（GluCl 和 HisCl）和组氨酸门控氯通道基因。检测到昆虫 γ-氨基丁酸（GABA）门控氯通道基因 Rdl 的三个同源物。其他 cysLGIC 组，如 nAChR 亚基，更为保守，具有明显的昆虫同源物。cysLGIC 家族成员介导内源性化学神经传递，是杀虫剂的主要靶标。本文讨论了与二斑叶螨家族成员的身份和特征相关的毒理学意义。我们进一步揭示了与阿维菌素抗性相关的不同 GluCl 通道亚基（Tu_GluCl1 和 Tu_GluCl3）中已知和新突变的积累，并提供了遗传证据证明其因果关系。我们的研究为探索二斑叶螨 cysLGIC 亚基作为当前和未来化学防治策略的潜在分子靶标提供了有用的毒理学见解。
