Journal Article

Yeast-derived volatiles orchestrate an insect-yeast mutualism with oriental armyworm moths

Chen, Run, Ma, Baiwei, Ai, Dong, Chang, Hetan, Wang, Guirong, Hansson, Bill S., Wang, Jiayu, Ren, Bingzhong, Guo, Mengbo, Liu, Xiaolan

2025

Overview

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. Interactions among insects, plants, and microorganisms are fundamental for ecosystem function. This study focuses on the attraction of oriental armyworm moths to yeast-fermented nectar and finds that isoamyl alcohol, a yeast-derived compound, activates specific olfactory neurons in the moths, enhancing yeast dispersal and moth reproduction.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 45/23 / 45/91 / 631/158/856 / 631/181/2481 / 631/378/2624/2625 / Alcohol / Alcohols / Allelochemicals / Animals / Antennal lobe / Behavior, Animal / Butterflies & moths / Ecological function / Ecosystem dynamics / Ecosystems / Female / Flowers & plants / Foraging behavior / Glomerulus / Humanities and Social Sciences / Insects / Isopentyl alcohol / Metschnikowia - metabolism / Metschnikowia - physiology / Microorganisms / Moths - microbiology / Moths - physiology / multidisciplinary / Mutualism / Nectar / Neurons / Odorant receptors / Olfactory glomeruli / Olfactory neurons / Olfactory receptor neurons / Olfactory Receptor Neurons - drug effects / Olfactory Receptor Neurons - metabolism / Olfactory Receptor Neurons - physiology / Pentanols - metabolism / Pentanols - pharmacology / Plant nectar / Plant Nectar - metabolism / Pollen / Pollen - metabolism / Pollination / Reproduction / Reproductive behavior / Science / Science (multidisciplinary) / Sensory neurons / Symbiosis - physiology / VOCs / Volatile compounds / Volatile organic compounds / Volatile Organic Compounds - metabolism / Volatile Organic Compounds - pharmacology / Yeast