Bombykol (EZ) is the single component of the female sex pheromone in the silkmoth Bombyx mori. EZ alone evokes full courtship behaviors from conspecific males; however, its geometric isomer (EE) was consistently detected in the pheromone glands (PG) of 16 B. mori strains and a field population of the wild silkmoth Bombyx mandarina, which also uses EZ as the single pheromone component. We investigated the pheromonal activities of EE using a commercial hybrid strain of B. mori, Kinshu × Showa. The behavioral assay demonstrated that a 104-105-fold higher dose of EE than EZ was able to elicit behavioral responses from males. To elucidate whether the trace contaminant of EZ in the EE standard is responsible for these responses, we examined the responses of male antennae to EE using a gas chromatograph-electroantennographic detector system (GC-EAD). The EE, at high doses elicited marginal responses from the male antennae. We next examined antennal and behavioral responses of B. mori whose BmOR1 gene, which is responsible for the reception of bombykol, was knocked out. The knockout of BmOR1 resulted in the complete loss of antennal and behavioral responses to EE and EZ, demonstrating that if EE itself is active, it induces these responses via the incidental stimulation of BmOR1, not via the stimulation of EE-specific receptors. The existence of EE in the PG of B. mori and B. mandarina is discussed from the viewpoints of pheromone biosynthesis and the evolution of pheromone communication systems.

中文翻译：

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在蚕蛾家蚕信息素腺中，bombykol异构体（10E，12E）-10,12-hexadecadien-1-ol的激素活性。

家蚕（EZ）是蚕蛾家蚕中女性信息素的单一成分。仅EZ就能引起同种男性的全面求爱行为。但是，其几何异构体（EE）始终在16种桑蚕B.菌株的信息素腺（PG）和野生蚕蛾Bombyx mandarina的田间种群中被检测到，后者也使用EZ作为单一信息素成分。我们使用商业化的桑蚕B. mori，金州×昭和杂交菌株调查了EE的信息素活性。行为分析表明，与EZ相比，EE剂量高104-105倍，能够引起男性的行为反应。为了阐明EE标准中微量的EZ污染物是否对这些响应负责，我们使用气相色谱-电子耳蜗探测器系统（GC-EAD）检查了雄性触角对EE的响应。高剂量的EE引起雄性触角的边缘反应。接下来，我们检查了B. mori的触角和行为反应，该基因的BmOR1基因（负责负责bombykol的接收）被敲除。BmOR1的敲除导致对EE和EZ的触角和行为反应完全丧失，表明如果EE本身是活跃的，它将通过BmOR1的偶然刺激而不是通过EE特异性受体的刺激来诱导这些反应。从信息素的生物合成和信息素通讯系统的发展的角度，探讨了桑蚕和普通芽孢杆菌PG中EE的存在。被淘汰了。BmOR1的敲除导致对EE和EZ的触角和行为反应完全丧失，表明如果EE本身是活跃的，它将通过BmOR1的偶然刺激而不是通过EE特异性受体的刺激来诱导这些反应。从信息素的生物合成和信息素通讯系统的发展的角度，探讨了桑蚕和普通芽孢杆菌PG中EE的存在。被淘汰了。BmOR1的敲除导致对EE和EZ的触角和行为反应完全丧失，表明如果EE本身是活跃的，它将通过BmOR1的偶然刺激而不是通过EE特异性受体的刺激来诱导这些反应。从信息素的生物合成和信息素通讯系统的发展的角度，探讨了桑蚕和普通芽孢杆菌PG中EE的存在。