Cui Xiaoning, Liu Deguang, Sun Keke, He Yang, Shi Xiaoqin
State Key Laboratory of Crop Stress Biology for Arid Areas (Northwest A&F University), Yangling, Shaanxi Province, China.
College of Plant Protection, Northwest A&F University, Yangling, Shaanxi Province, China.
J Econ Entomol. 2018 May 28;111(3):1420-1432. doi: 10.1093/jee/toy066.
The apple buprestid beetle, Agrilus mali Matsumura (Coleoptera: Buprestidae), can respond to various volatiles, but the underlying mechanism of odorant perception for this insect is poorly understood. Here, we cloned A. mali's odorant-binding proteins 3 (AmalOBP3) and 8 (AmalOBP8) and characterized their expression patterns and binding profiles. Sequence and phylogenetic analyses showed that AmalOBP3 and AmalOBP8 were distributed in the classic and minus-C OBP subfamily, respectively. AmalOBP3 was specifically and abundantly expressed in antennae of both sexes. AmalOBP8 displayed high transcript levels in antennae of both sexes, abdomens of males, and wings of both sexes. Both AmalOBPs exhibited much higher expression in male antennae than in female antennae, suggesting that they could be important in perception of male-specific olfactory cues (e.g., some sex pheromones). Out of the 40 odorant ligands tested, AmalOBP3 and AmalOBP8 bound to 15 and 21 different odorants, respectively, indicating a distinct and selective binding profile for them. Both AmalOBPs seemed to have very strong binding affinity to aliphatic alcohols and aldehydes with 12 to 15 carbon atoms. Alcohols, esters, and terpenoids were more likely to be good ligands for both AmalOBPs than aldehydes and alkanes. Together with its broad expression in different tissues, strong binding with higher numbers of putative ligands for AmalOPB8 means that this protein can have more extensive functional roles in chemosensation of A. mali. Our results provide insights into the molecular basis of chemosensation in A. mali, as well as a basis for developing detection, monitoring, and management tools for this serious pest.
苹果吉丁虫，即苹果窄吉丁（Agrilus mali Matsumura，鞘翅目：吉丁甲科），能够对多种挥发性物质产生反应，但对于这种昆虫嗅觉感知的潜在机制，人们了解甚少。在此，我们克隆了苹果窄吉丁的气味结合蛋白3（AmalOBP3）和8（AmalOBP8），并对它们的表达模式和结合谱进行了表征。序列和系统发育分析表明，AmalOBP3和AmalOBP8分别分布在经典OBP亚家族和负C OBP亚家族中。AmalOBP3在两性触角中特异性且大量表达。AmalOBP8在两性触角、雄性腹部以及两性翅膀中均表现出高转录水平。两种AmalOBP在雄性触角中的表达均远高于雌性触角，这表明它们在感知雄性特异性嗅觉线索（如某些性信息素）方面可能发挥重要作用。在所测试的40种气味配体中，AmalOBP3和AmalOBP8分别与15种和21种不同的气味剂结合，表明它们具有独特的选择性结合谱。两种AmalOBP似乎对含有12至15个碳原子的脂肪醇和醛具有非常强的结合亲和力。醇类、酯类和萜类比醛类和烷烃更有可能是两种AmalOBP的良好配体。AmalOPB8在不同组织中广泛表达，且与更多假定配体具有强结合能力，这意味着该蛋白在苹果窄吉丁的化学感知中可能具有更广泛的功能作用。我们的研究结果为苹果窄吉丁化学感知的分子基础提供了见解，也为开发针对这种严重害虫的检测、监测和管理工具奠定了基础。
