Key Laboratory of Tea Quality and Safety Control, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China.
College of Agriculture and Food Science, Zhejiang A & F University, Hangzhou, China.
J Insect Physiol. 2019 Jul;116:17-24. doi: 10.1016/j.jinsphys.2019.04.005. Epub 2019 Apr 19.
Pheromone-binding proteins (PBPs) are considered to play critical roles in sex pheromone detection. Lepidopteran moths can be divided into two taxa, those that use Type-I sex pheromones, such as C10-C18 unsaturated aldehydes, alcohols and acetates, and those that use Type-II pheromones, which are C17-C23 polyunsaturated hydrocarbons and their epoxide derivatives. To date, nearly all the characterized PBPs have been reported in moths with Type-I sex pheromones, and the physiological functions of PBPs in moths that use Type-II sex pheromones remains unclear. In the present study we functionally examine EoblPBP1 in Ectropis obliqua Prout, an important geometrid moth pest that uses Type-II sex pheromones. The phylogenetic analysis of the sequence indicated that EoblPBP1 clustered together with ScerPBP1, a geometrid PBP for detecting Type-II sex pheromones. Scanning electron microscopy showed that E. obliqua moths of both sexes mainly had six types of antennal sensilla, including two types of sensilla trichodea, Str-I and Str-II, sensilla basiconica (Sba), sensilla styloconica (Sst), sensilla chaetica (Sch) and sensilla auricillica (Sau). Of these, Str-I was confirmed to be male moth-specific and had five different subtypes. Fluorescence in situ hybridization revealed that EoblPBP1 was primarily expressed at the base of Str-I. A comparative binding assay showed that recombinant EoblPBP1 bound three sex pheromone components of E. obliqua, demonstrating its involvement in the detection of Type-II sex pheromones. Besides, EoblPBP1 also highly bound unsaturated acetates pheromones and the green leaf volatiles. These results indicate that PBP1 is associated with detecting Type-II sex pheromones in E. obliqua but cannot differentiate Type-II sex pheromones from Type-I sex pheromones or green leaf volatiles. Our findings provide a foundation for further study on molecular basis of Type-II sex pheromone recognition in lepidopteran moths.
信息素结合蛋白（PBPs）被认为在性信息素检测中发挥着关键作用。鳞翅目飞蛾可分为两类，一类使用 I 型性信息素，如 C10-C18 不饱和醛、醇和醋酸盐，另一类使用 II 型信息素，即 C17-C23 多不饱和烃及其环氧化物衍生物。迄今为止，几乎所有鉴定的 PBP 都在使用 I 型性信息素的飞蛾中被报道，而使用 II 型性信息素的飞蛾中 PBP 的生理功能仍不清楚。在本研究中，我们对使用 II 型性信息素的重要尺蠖蛾科害虫东方尺蠖（Ectropis obliqua Prout）中的 EoblPBP1 进行了功能研究。序列的系统发育分析表明，EoblPBP1 与 ScerPBP1 聚在一起，ScerPBP1 是一种用于检测 II 型性信息素的尺蠖 PBP。扫描电子显微镜显示，雌雄东方尺蠖的触角主要有 6 种类型的感觉器，包括两种感觉器毛形感器（Str-I 和 Str-II）、感觉器锥形感器（Sba）、感觉器柱状感器（Sst）、感觉器刺形感器（Sch）和感觉器耳形感器（Sau）。其中，Str-I 被确认为雄性蛾特有的，并有 5 种不同的亚型。荧光原位杂交显示，EoblPBP1 主要在 Str-I 的基部表达。比较结合测定表明，重组 EoblPBP1 结合了东方尺蠖的 3 种性信息素成分，表明其参与了 II 型性信息素的检测。此外，EoblPBP1 还高度结合不饱和醋酸酯信息素和绿叶挥发物。这些结果表明，PBP1 与东方尺蠖 II 型性信息素的检测有关，但不能区分 II 型性信息素与 I 型性信息素或绿叶挥发物。我们的研究结果为进一步研究鳞翅目飞蛾 II 型性信息素识别的分子基础提供了依据。
