Identification of receptors of main sex-pheromone components of three Lepidopteran species
Identification of receptors of main sex-pheromone components of three Lepidopteran species
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DOI：
10.1111/j.1460-9568.2008.06429.x
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发表时间：
2008-09-01
影响因子：
3.4
通讯作者：
Nishioka, Takaaki
中科院分区：
文献类型：
--
作者：
Mitsuno, Hidefumi;Sakurai, Takeshi;Nishioka, Takaaki
雄蛾辨别同种雌蛾释放的性信息素。尽管已经在500多种蛾身上鉴定出了性信息素的化学成分，但只有三种成分在家蚕和绿色日光夜蛾中得到了受体的鉴定。本文报道了三种小菜蛾、粘虫和二化蛾的主要性信息素受体的鉴定。我们分别从小菜蛾、小菜蛾和印度小菜蛾中克隆了可能的性信息素受体基因PxOR1、MsOR1和DiOR1。这三个基因中的每一个都与Or83b同源基因在雄性嗅觉感受器神经元(ON)中唯一表达，ON周围有表达信息素结合蛋白(PBP)基因的支持细胞。通过双电极电压钳记录，我们检测了非洲爪哇卵母细胞与OR83b家族蛋白共表达PxOR1、MsOR1或DiOR1的配基特异性。在3种蛾的7种性信息素成分中，卵母细胞仅对相应种的主要性信息素成分有剂量依赖性的反应。在我们的研究中，PBPs对于受体的配基特异性并不是必不可少的。在昆虫嗅觉受体的系统发育树上，目前和以前的研究中发现的6个性信息素受体属于同一亚科，但与蛾类的分类无关。最有可能的是，性信息素受体是在飞蛾物种形成之前从祖先的性信息素受体随机进化而来的，其配基特异性在物种形成后被当地氨基酸序列的突变所改变。
Male moths discriminate conspecific female-emitted sex pheromones. Although the chemical components of sex pheromones have been identified in more than 500 moth species, only three components in Bombyx mori and Heliothis virescens have had their receptors identified. Here we report the identification of receptors for the main sex-pheromone components in three moth species, Plutella xylostella, Mythimna separata and Diaphania indica. We cloned putative sex-pheromone receptor genes PxOR1, MsOR1 and DiOR1 from P. xylostella, M. separata and D. indica, respectively. Each of the three genes was exclusively expressed with an Or83b orthologous gene in male olfactory receptor neurons (ORNs) that are surrounded by supporting cells expressing pheromone-binding-protein (PBP) genes. By two-electrode voltage-clamp recording, we tested the ligand specificity of Xenopus oocytes co-expressing PxOR1, MsOR1 or DiOR1 with an OR83b family protein. Among the seven sex-pheromone components of the three moth species, the oocytes dose-dependently responded only to the main sex-pheromone component of the corresponding moth species. In our study, PBPs were not essential for ligand specificity of the receptors. On the phylogenetic tree of insect olfactory receptors, the six sex-pheromone receptors identified in the present and previous studies are grouped in the same subfamily but have no relation with the taxonomy of moths. It is most likely that sex-pheromone receptors have randomly evolved from ancestral sex-pheromone receptors before the speciation of moths and that their ligand specificity was modified by mutations of local amino acid sequences after speciation.