Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, Guangdong, China.
Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, Guangdong, China.
Int J Biol Macromol. 2024 Oct;278(Pt 3):134905. doi: 10.1016/j.ijbiomac.2024.134905. Epub 2024 Aug 20.
Aethina tumida (small hive beetle, SHB) is a rapidly spreading invasive parasite of bee colonies. The olfactory system plays a key role in insect behavior, and odorant-binding proteins (OBPs) are involved in the first step of the olfactory signal transduction pathway and the detection of host volatiles. However, the olfactory mechanism of OBPs in SHB-localized bee colonies is unclear. In this study, electroantennogram (EAG) and behavioral bioassay showed that only three compounds (2-heptanone, ocimene, and ethyl palmitate) from bee colonies triggered high electrophysiological and behavioral responses. Three antenna-specific OBP genes (OBP6, OBP11, and OBP19) were identified, and they were significantly expressed on adult days 6-7. Furthermore, by combining RNA interference (RNAi) with EAG, olfactometer bioassay, competitive fluorescence binding assays, and molecular docking, we found that these three OBP genes were involved in the recognition of 2-heptanone and ethyl palmitate, and AtumOBP6 is also involved in the recognition of ocimene. These data indicate that AtumOBP6, AtumOBP11, and AtumOBP19 play an important role in the olfactory response to bee colony volatiles. Our results provide new insights into the functions of the OBP families in A. tumida and help to explore more potential target genes for environmentally friendly pest control strategies.
大蜡螟（小蜂蜡螟，SHB）是一种迅速传播的蜜蜂寄生虫。嗅觉系统在昆虫行为中起着关键作用，气味结合蛋白（OBP）参与嗅觉信号转导途径的第一步和宿主挥发物的检测。然而，SHB 定位的蜜蜂群体中 OBPs 的嗅觉机制尚不清楚。在这项研究中，触角电位（EAG）和行为生物测定表明，只有三种来自蜜蜂群体的化合物（2-庚酮、罗勒烯和棕榈酸乙酯）引发了高的电生理和行为反应。鉴定出三个触角特异性 OBP 基因（OBP6、OBP11 和 OBP19），它们在成虫第 6-7 天表达显著。此外，通过将 RNA 干扰（RNAi）与 EAG、嗅觉仪生物测定、竞争荧光结合测定和分子对接相结合，我们发现这三个 OBP 基因参与了对 2-庚酮和棕榈酸乙酯的识别，并且 AtumOBP6 也参与了对罗勒烯的识别。这些数据表明，AtumOBP6、AtumOBP11 和 AtumOBP19 在对蜜蜂群体挥发物的嗅觉反应中起着重要作用。我们的研究结果为 A. tumida 中 OBP 家族的功能提供了新的见解，并有助于探索更多潜在的环保害虫防治策略的目标基因。
