抑制性谷氨酸受体(IGluRs)通道及其相关杀虫剂的作用

抑制性谷氨酸受体(IGluRs)属于半胱氨酸环配体门控离子通道超家族,主要介导神经和肌肉细胞中抑制性的神经传递,目前仅在无脊椎动物中发现,在脊椎动物中尚未发现,因此是高选择性杀虫剂的理想靶标。IGluRs主要分布在无脊椎动物的神经和肌肉组织中,对控制吞咽、运动、感知和保幼激素的生物合成等可能起关键作用。人们对IGluRs的了解大多来自于对线虫和模式昆虫的研究,目前在线虫中共发现了4种α亚基和1种β亚基,是否有一种新的亚基类型如γ亚基尚不确定,从昆虫体内仅克隆了α亚基。就生理功能和药理特性而言,IGluRs与γ-氨基丁酸(GABA)受体最为类似,但其氨基酸序列却与甘氨酸受体相似性最高。作用于IGluRs的杀虫剂包括阿维菌素/美倍霉素类、苯基吡唑类杀虫剂氟虫腈以及吲哚二萜类化合物Nodulisporic acid等。对IGluRs的生理功能、分子特性、药理性质及相关杀虫剂的作用机理等的研究进展进行了综述。

Inhibitory Glutamate Receptor Channels and Related Insecticides

Inhibitory glutamate receptors (IGluRs) are members of the "Cys-loop" superfamily of ligand-gated ion channels.They mediate synaptic inhibition in neurons and expressed extrajunctionally in striated muscles.Until now,IGluRs channels are found only in invertebrates,and are therefore ideal insecticide targets with high selectivity.IGluRs are found both in neural and muscle tissues in invertebrates.They may play key roles in regulating swallow,locomotion,sense and juvenile hormone biosynthesis.Most of the knowledge about IGluRs came from studies on nematodes and model insects. All together four α subunits and one β subunit are found in nematodes but it is unknown whether a γ subunit exists.Only α subunit is cloned from insect.IGluRs are most similar to GABA receptors on the function of physiology and pharmacology. However,the amino acid sequences of cloned IGluRs are most similar to those of glycine receptor.The insecticides acting on IGluRs are avermectin/milbemycin,fipronil,a phenylpyrazole insecticide,and nodulisporic acid,a novel indole diterpene.The research progress of IGluRs in physiological function,molecular and pharmacological properties,and the mode of action of related insecticides was reviewed.