PDF(Pubmed)
Abstract：
Chemosensory proteins (CSPs) are highly efficient carry tools to bind and deliver hydrophobic compounds, which play an important role in the chemosensory process in insects. The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a cosmopolitan pest that attacks cruciferous crops. However, the detailed physiological functions of CSPs in P. xylostella remain limited to date. Here, we identified a typical CSP, named PxylCSP18, in P. xylostella and investigated its expression patterns and binding properties of volatiles. PxylCSP18 was highly expressed in antennae and head (without antennae), and the expression level in the male antennae of P. xylostella was obviously higher than that in the female antennae. Moreover, PxylCSP18 has a relatively broad binding spectrum. Fluorescence competitive binding assays showed that PxylCSP18 had strong binding abilities with 14 plant volatiles (Ki < 10 μM) that were repellent or attractive to P. xylostella. Notably, PxylCSP18 had no significant binding affinity to (Z)-11-hexadecenal, (Z)-11-hexadecenyl acetate, and (Z)-11-hexadecenyl alcolol, which are the pheromone components of P. xylostella. The attractive effects of trans-2-hexen-1-ol and isopropyl isothiocyanate to male adults and the attractive effects of isopropyl isothiocyanate and the repellent effects of linalool to female adults were significantly decreased after knocked down the expression of PxylCSP18. Our results revealed that PxylCSP18 might play an important role in host plant detection, avoidance of unsuitable hosts, and selection of oviposition sites; however, it does not participate in mating behavior. Overall, these results extended our knowledge on the CSP-related functions, which provided insightful information about CSP-targeted insecticides.
摘要：
化学感觉蛋白（CSP）是结合和递送疏水性化合物的高效携带工具，在昆虫的化学感应过程中起着重要作用。小菜蛾,小菜蛾（鳞翅目：小菜蛾科），是一种攻击十字花科作物的世界性害虫。然而,迄今为止，小菜蛾中CSP的详细生理功能仍然有限。这里,我们确定了一个典型的CSP,命名为PxylCSP18，在P.xylostella，并研究其表达模式和挥发物的结合特性。PxylCSP18在触角和头部（无触角）中高度表达，小菜蛾雄性触角中的表达水平明显高于雌性触角。此外，PxylCSP18具有相对宽的结合谱。荧光竞争性结合实验表明，PxylCSP18与14种植物挥发物（Ki<10μM）具有很强的结合能力，这些植物挥发物对小菜蛾具有排斥或吸引力。值得注意的是,PxylCSP18对（Z）-11-十六烯醛没有明显的结合亲和力，(Z)-11-十六烯基乙酸酯,和（Z）-11-十六碳烯基醇，是P.xylostella的信息素成分。反式-2-己烯-1-醇和异硫氰酸异丙酯对成年男性的吸引作用，异硫氰酸异丙酯的吸引作用和芳樟醇对成年女性的驱避作用在下调PxylCSP18的表达后明显下降。我们的结果表明，PxylCSP18可能在寄主植物检测中发挥重要作用，避免不合适的宿主，和产卵地点的选择；然而，它不参与交配行为。总的来说,这些结果扩展了我们对CSP相关函数的了解，提供了有关CSP靶向杀虫剂的有见地的信息。
