Data from: Experimental evolution of an emerging plant virus in host genotypes that differ in their susceptibility to infection

This study evaluates the extent to which genetic differences among host individuals from the same species conditions the evolution of a plant RNA virus. We performed a three-fold replicated evolution experiment in which Tobacco etch potyvirus isolate At17b (TEV-At17b), adapted to Arabidopsis thaliana ecotype Ler-0, was serially passaged in five genetically heterogeneous ecotypes of A. thaliana. After 15 passages we found that evolved viruses improved their fitness, showed higher infectivity and stronger virulence in their local host ecotypes. The genome of evolved lineages was sequenced and putative adaptive mutations identified. Host-driven convergent mutations have been identified. Evidences supported selection for increased translational efficiency. Next, we sought for the specificity of virus adaptation by infecting all five ecotypes with all 15 evolved virus populations. We found that some ecotypes were more permissive to infection than others, and that some evolved virus isolates were more specialist/generalist than others. The bipartite network linking ecotypes with evolved viruses was significantly nested but not modular, suggesting that hard to infect ecotypes were infected by generalist viruses whereas easy to infect ecotypes were infected by all viruses, as predicted by a gene-for-gene model of infection.本研究旨在评估同一物种宿主个体间的遗传差异对植物RNA病毒演化的调控程度。我们开展了三组重复演化实验：将适应拟南芥（Arabidopsis thaliana）生态型Ler-0的烟草蚀刻马铃薯Y病毒（Tobacco etch potyvirus）分离株At17b（TEV-At17b），在5种具有遗传异质性的拟南芥生态型中进行连续传代。经过15次传代后，我们发现演化后的病毒种群在其对应的宿主生态型中适合度显著提升，感染力与致病力均有所增强。研究人员对演化谱系的基因组进行测序并鉴定出潜在的适应性突变，同时发现了宿主驱动的趋同突变，实验结果支持病毒受到选择以提升翻译效率的推论。随后，我们通过用全部15个演化病毒种群感染全部5种宿主生态型，探究了病毒适应性的宿主特异性。结果显示，部分生态型的病毒感染易感性相较于其他生态型更高，且部分演化病毒分离株的宿主专化性与泛化性存在差异。连接宿主生态型与演化病毒的二分网络呈现出显著的嵌套结构，但不具备模块化特征，这表明难以被感染的生态型仅能被泛化型病毒侵染，而易被感染的生态型则可被所有病毒侵染，这与基因对基因模型（gene-for-gene model）的预测结果一致。