Ma Baiwei, Chang Hetan, Guo Mengbo, Ai Dong, Wang Jiayu, Chen Run, Liu Xiaolan, Ren Bingzhong, Hansson Bill S, Wang Guirong
Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Synthetic Biology Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
Nat Commun. 2025 Feb 10;16(1):1479. doi: 10.1038/s41467-025-56354-3.
Interactions among insects, plants, and microorganisms are fundamental to ecosystem dynamics, with floral nectar and pollen serving as key resources for various organisms. Yeasts, such as Metschnikowia reukaufii, commonly found in nectar, influence nectarial attraction through volatile compounds (VOCs), yet the underlying biological mechanisms remain elusive. Here, we show that isoamyl alcohol, a prominent yeast VOC, attracts oriental armyworm moths (Mythimna separata) to pollen-rich, yeast-fermented nectar. In a series of electrophysiological and behavioral assays, we show that isoamyl alcohol activates a single class of highly specific olfactory sensory neurons expressing the olfactory receptor MsepOR8. In the moth antennal lobe, these neurons target the AM2 glomerulus, which responds to isoamyl alcohol. Genetic disruption of MsepOR8 leads to complete abolition of both physiological and behavioral responses to isoamyl alcohol, resulting in an impaired ability to locate nectar sources. Moreover, we show that isoamyl alcohol-induced foraging behavior fosters a mutualistic relationship between yeast and moths to some extent, enhancing yeast dispersal and increasing moth reproductive success. Our results unveil a highly specific mechanism by which a yeast-derived VOC facilitates insect-yeast mutualism, providing insights into insect-microbe interactions within pollination ecosystems.
昆虫、植物和微生物之间的相互作用是生态系统动态变化的基础，花蜜和花粉是各种生物的关键资源。常见于花蜜中的酵母，如鲁考夫梅奇酵母（Metschnikowia reukaufii），通过挥发性化合物（VOCs）影响花蜜的吸引力，但其潜在的生物学机制仍不清楚。在这里，我们表明，异戊醇是一种重要的酵母挥发性有机化合物，它能吸引东方粘虫蛾（Mythimna separata）到富含花粉、经酵母发酵的花蜜上。在一系列电生理和行为试验中，我们表明异戊醇激活了一类单一的、高度特异性的嗅觉感觉神经元，这些神经元表达嗅觉受体MsepOR8。在蛾类触角叶中，这些神经元靶向对异戊醇有反应的AM2小球。MsepOR8的基因破坏导致对异戊醇的生理和行为反应完全消失，导致定位花蜜来源的能力受损。此外，我们表明异戊醇诱导的觅食行为在一定程度上促进了酵母和蛾类之间的互利关系，增强了酵母的传播并提高了蛾类的繁殖成功率。我们的结果揭示了一种高度特异性的机制，即酵母衍生的挥发性有机化合物促进昆虫与酵母的互利共生，为授粉生态系统中昆虫与微生物的相互作用提供了见解。
