Antony Binu, Johny Jibin, Aldosari Saleh A
Chair of Date Palm Research, Department of Plant Protection, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia.
Front Physiol. 2018 Mar 21;9:252. doi: 10.3389/fphys.2018.00252. eCollection 2018.
In insects, perception of the environment-food, mates, and prey-is mainly guided by chemical signals. The dynamic process of signal perception involves transport to odorant receptors (ORs) by soluble secretory proteins, odorant binding proteins (OBPs), which form the first stage in the process of olfactory recognition and are analogous to lipocalin family proteins in vertebrates. Although OBPs involved in the transport of pheromones to ORs have been functionally identified in insects, there is to date no report for Coleoptera. Furthermore, there is a lack of information on olfactory perception and the molecular mechanism by which OBPs participate in the transport of aggregation pheromones. We focus on the red palm weevil (RPW) , the most devastating quarantine pest of palm trees worldwide. In this work, we constructed libraries of all OBPs and selected antenna-specific and highly expressed OBPs for silencing through RNA interference. Aggregation pheromone compounds, 4-methyl-5-nonanol (ferrugineol) and 4-methyl-5-nonanone (ferruginone), and a kairomone, ethyl acetate, were then sequentially presented to individual RPWs. The results showed that antenna-specific aids in the capture and transport of ferrugineol to ORs. Silencing of , which is responsible for pheromone binding, significantly disrupted pheromone communication. Study of odorant perception in palm weevil is important because the availability of literature regarding the nature and role of olfactory signaling in this insect may reveal likely candidates representative of animal olfaction and, more generally, of molecular recognition. Knowledge of OBPs recognizing the specific pheromone ferrugineol will allow for designing biosensors for the detection of this key compound in weevil monitoring in date palm fields.
在昆虫中，对环境（食物、配偶和猎物）的感知主要由化学信号引导。信号感知的动态过程涉及由可溶性分泌蛋白——气味结合蛋白（OBP）将气味分子转运至气味受体（OR），OBP构成嗅觉识别过程的第一阶段，类似于脊椎动物中的脂质运载蛋白家族蛋白。尽管在昆虫中已在功能上鉴定出参与将信息素转运至OR的OBP，但迄今为止尚未有关于鞘翅目的报道。此外，关于嗅觉感知以及OBP参与聚集信息素转运的分子机制的信息也很缺乏。我们聚焦于红棕象甲（RPW），它是全球棕榈树最具毁灭性的检疫性害虫。在这项工作中，我们构建了所有OBP的文库，并选择触角特异性且高表达的OBP通过RNA干扰进行沉默。然后依次向单个红棕象甲呈现聚集信息素化合物4-甲基-5-壬醇（锈红醇）和4-甲基-5-壬酮（锈红酮）以及一种利它素乙酸乙酯。结果表明，触角特异性有助于将锈红醇捕获并转运至OR。负责信息素结合的OBP的沉默显著扰乱了信息素通讯。研究象甲的气味感知很重要，因为关于这种昆虫嗅觉信号的性质和作用的文献资料可能会揭示出代表动物嗅觉以及更普遍的分子识别的潜在候选物。了解识别特定信息素锈红醇的OBP将有助于设计生物传感器，用于在枣椰树果园象甲监测中检测这种关键化合物。
