Department of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, UK.
Department of Pathobiology and Population Sciences, The Royal Veterinary College, Hawkshead Lane, Hatfield, Herfordshire, AL9 7TA, UK.
Ecol Lett. 2019 May;22(5):826-837. doi: 10.1111/ele.13240. Epub 2019 Mar 13.
The mammalian gut microbiota is considered pivotal to host fitness, yet the determinants of community composition remain poorly understood. Laboratory studies show that environmental factors, particularly diet, are important, while comparative work emphasises host genetics. Here, we compare the influence of host genetics and the environment on the microbiota of sympatric small mammal species (mice, voles, shrews) across multiple habitats. While sharing a habitat caused some microbiota convergence, the influence of species identity dominated. In all three host genera examined, an individual's microbiota was more similar to conspecifics living elsewhere than to heterospecifics at the same site. Our results suggest this species-specificity arises in part through host-microbe codiversification. Stomach contents analysis suggested that diet also shapes the microbiota, but where diet is itself influenced by species identity. In this way, we can reconcile the importance of both diet and genetics, while showing that species identity is the strongest predictor of microbiota composition.
哺乳动物肠道微生物群被认为对宿主健康至关重要，但群落组成的决定因素仍知之甚少。实验室研究表明，环境因素，特别是饮食，非常重要，而比较工作则强调宿主遗传学。在这里，我们比较了宿主遗传学和环境对多种生境中同域小型哺乳动物物种（小鼠、田鼠、鼩鼱）微生物群的影响。尽管共享生境导致了一些微生物群的趋同，但物种身份的影响占主导地位。在所研究的三个宿主属中，个体的微生物群与生活在其他地方的同物种个体比与同一地点的异物种个体更相似。我们的结果表明，这种特异性部分是通过宿主-微生物共同进化产生的。胃内容物分析表明，饮食也塑造了微生物群，但饮食本身受到物种身份的影响。通过这种方式，我们可以调和饮食和遗传的重要性，同时表明物种身份是微生物群落组成的最强预测因子。
