PDF(Pubmed)
Abstract：
Seaweeds are colonized by a microbial community, which can be directly linked to their performance. This community is shaped by an interplay of stochastic and deterministic processes, including mechanisms which the holobiont host deploys to manipulate its associated microbiota. The Anna Karenina principle predicts that when a holobiont is exposed to suboptimal or stressful conditions, these host mechanisms may be compromised. This leads to a relative increase of stochastic processes that may potentially result in the succession of a microbial community harmful to the host. Based on this principle, we used the variability in microbial communities (i.e., beta diversity) as a proxy for stability within the invasive holobiont Gracilaria vermiculophylla during a simulated invasion in a common garden experiment. Independent of host range, host performance declined at elevated temperature (22°C) and disease incidence and beta diversity increased. Under thermally stressful conditions, beta diversity increased more in epibiota from native populations, suggesting that epibiota from non-native holobionts are thermally more stable. This pattern reflects an increase in deterministic processes acting on epibiota associated with non-native hosts, which in the setting of a common garden can be assumed to originate from the host itself. Therefore, these experimental data suggest that the invasion process may have selected for hosts better able to maintain stable microbiota during stress. Future studies are needed to identify the underlying host mechanisms.
摘要：
海藻被微生物群落定植，这可以直接与他们的表现联系起来。这个社区是由随机和确定性过程的相互作用形成的，包括holobiont宿主部署来操纵其相关微生物群的机制。安娜·卡列尼娜原理预测，当一个完整的人暴露在次优或压力条件下，这些主机机制可能会受到损害。这导致随机过程的相对增加,这可能潜在地导致对宿主有害的微生物群落的演替。基于这个原则,我们使用了微生物群落的变异性(即，β多样性）作为在普通花园实验中模拟入侵过程中侵入性完整的龙须菜内部稳定性的代表。独立于主机范围，在升高的温度（22°C）下，宿主性能下降，疾病发生率和β多样性增加。在热应力条件下，β多样性在本地种群的表观生物群中增加更多，表明来自非天然全生物的表生物群在热上更稳定。这种模式反映了作用于与非本地宿主相关的表观生物群的确定性过程的增加，在公共花园的设置中，可以假定它来自宿主本身。因此,这些实验数据表明，入侵过程可能选择了能够在应激期间更好地保持稳定微生物群的宿主。需要进一步的研究来确定潜在的宿主机制。
