Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA.
Evolution. 2012 Feb;66(2):349-62. doi: 10.1111/j.1558-5646.2011.01454.x. Epub 2011 Oct 5.
The comparative structure of bacterial communities among closely related host species remains relatively unexplored. For instance, as speciation events progress from incipient to complete stages, does divergence in the composition of the species' microbial communities parallel the divergence of host nuclear genes? To address this question, we used the recently diverged species of the parasitoid wasp genus Nasonia to test whether the evolutionary relationships of their bacterial microbiotas recapitulate the Nasonia phylogenetic history. We also assessed microbial diversity in Nasonia at different stages of development to determine the role that host age plays in microbiota structure. The results indicate that all three species of Nasonia share simple larval microbiotas dominated by the γ-proteobacteria class; however, bacterial species diversity increases as Nasonia develop into pupae and adults. Finally, under identical environmental conditions, the relationships of the microbial communities reflect the phylogeny of the Nasonia host species at multiple developmental stages, which suggests that the structure of an animal's microbial community is closely allied with divergence of host genes. These findings highlight the importance of host evolutionary relationships on microbiota composition and have broad implications for future studies of microbial symbiosis and animal speciation.
在密切相关的宿主物种中，细菌群落的比较结构仍然相对未知。例如，随着物种形成事件从初始阶段发展到完全阶段，物种微生物群落的组成是否与宿主核基因的分化平行？为了解决这个问题，我们使用最近分化的寄生蜂属 Nasonia 物种来测试它们的细菌微生物群的进化关系是否反映了 Nasonia 的系统发育历史。我们还评估了 Nasonia 在不同发育阶段的微生物多样性，以确定宿主年龄在微生物组结构中的作用。结果表明，Nasonia 的所有三个物种都具有简单的幼虫微生物群，主要由γ-变形菌纲组成；然而，随着 Nasonia 发育成蛹和成虫，细菌物种多样性增加。最后，在相同的环境条件下，微生物群落的关系反映了 Nasonia 宿主物种在多个发育阶段的系统发育，这表明动物微生物群落的结构与宿主基因的分化密切相关。这些发现强调了宿主进化关系对微生物群落组成的重要性，并对未来的微生物共生和动物物种形成研究具有广泛的意义。
