Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard Lyon 1, Unité Mixte de Recherche 5242, 69364 Lyon Cedex 07, France.
Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Ecole Normale Supérieure de Lyon, Centre National de la Recherche Scientifique, Université Claude Bernard Lyon 1, Unité Mixte de Recherche 5242, 69364 Lyon Cedex 07, France.
Cell Host Microbe. 2018 Jul 11;24(1):109-119.e6. doi: 10.1016/j.chom.2018.06.001. Epub 2018 Jun 28.
Animal-microbe facultative symbioses play a fundamental role in ecosystem and organismal health. Yet, due to the flexible nature of their association, the selection pressures that act on animals and their facultative symbionts remain elusive. Here we apply experimental evolution to Drosophila melanogaster associated with its growth-promoting symbiont Lactobacillus plantarum, representing a well-established model of facultative symbiosis. We find that the diet of the host, rather than the host itself, is a predominant driving force in the evolution of this symbiosis. Furthermore, we identify a mechanism resulting from the bacterium's adaptation to the diet, which confers growth benefits to the colonized host. Our study reveals that bacterial adaptation to the host's diet may be the foremost step in determining the evolutionary course of a facultative animal-microbe symbiosis.
动物-微生物兼性共生在生态系统和生物机体健康中发挥着基础性作用。然而，由于其关联的灵活性，作用于动物及其兼性共生体的选择压力仍然难以捉摸。在这里，我们应用实验进化方法研究与促进生长的共生菌植物乳杆菌相关的黑腹果蝇，这是兼性共生的一个成熟模型。我们发现，与其说是宿主，不如说是宿主的饮食，是这种共生关系进化的主要驱动力。此外，我们发现了一种由细菌适应饮食引起的机制，这种机制赋予了被殖民宿主生长优势。我们的研究表明，细菌对宿主饮食的适应可能是决定兼性动物-微生物共生进化过程的首要步骤。
