Data from: Gut microbiota modifies olfactory-guided microbial preferences and foraging decisions in Drosophila

The gut microbiota affects a wide spectrum of host physiological traits, including development [ 1–5 ], germline [ 6 ], immunity [ 7–9 ], nutrition [ 4, 10, 11 ], and longevity [ 12, 13 ]. Association with microbes also influences fitness-related behaviors such as mating [ 14 ] and social interactions [ 15, 16 ]. Although the gut microbiota is evidently important for host wellbeing, how hosts become associated with particular assemblages of microbes from the environment remains unclear. Here, we present evidence that the gut microbiota can modify microbial and nutritional preferences of Drosophila melanogaster. By experimentally manipulating the gut microbiota of flies subjected to behavioral and chemosensory assays, we found that fly-microbe attractions are shaped by the identity of the host microbiota. Conventional flies exhibit preference for their associated Lactobacillus, a behavior also present in axenic flies as adults and marginally as larvae. By contrast, fly preference for Acetobacter is primed by early-life exposure and can override the innate preference. These microbial preferences are largely olfactory guided and have profound impact on host foraging, as flies continuously trade off between acquiring beneficial microbes and balancing nutrients from food. Our study shows a role of animal microbiota in shaping host fitness-related behavior through their chemosensory responses, opening a research theme on the interrelationships between the microbiota, host sensory perception, and behavior.

肠道菌群（gut microbiota）会影响宿主的一系列生理性状，包括发育[1-5]、生殖系[6]、免疫[7-9]、营养[4,10,11]与寿命[12,13]。与微生物的定植关联还会影响宿主适合度相关的行为，例如交配[14]与社交互动[15,16]。尽管肠道菌群对宿主健康至关重要，但宿主如何从环境中获取特定的微生物群落，其机制仍未明确。本研究提供证据表明，肠道菌群可改变黑腹果蝇（Drosophila melanogaster）的微生物与营养偏好。通过对参与行为与化学感应（chemosensory）实验的果蝇肠道菌群进行实验性操控，我们发现果蝇与微生物的趋性受宿主菌群的种类所调控。常规饲养的果蝇表现出对其共生的乳杆菌属（Lactobacillus）的偏好，该行为在成年无菌（axenic）果蝇中存在，幼虫阶段仅表现出微弱偏好。与之相反，果蝇对醋杆菌属（Acetobacter）的偏好由早期生命暴露所诱导，且可逆转固有偏好。此类微生物偏好主要通过嗅觉介导，并对宿主的觅食行为产生深远影响——因为果蝇需要在获取有益微生物与平衡食物营养之间持续权衡。本研究揭示了动物菌群可通过化学感应反应调控宿主适合度相关行为的作用，为菌群、宿主感官感知与行为之间的相互关系开辟了全新的研究主题。