Istituto di Virologia Vegetale, Torino, Italy.
Mol Plant Microbe Interact. 2011 Dec;24(12):1562-72. doi: 10.1094/MPMI-05-11-0116.
Tomato (Solanum lycopersicum) can establish symbiotic interactions with arbuscular mycorrhizal (AM) fungi, and can be infected by several pathogenic viruses. Here, we investigated the impact of mycorrhization by the fungus Glomus mosseae on the Tomato spotted wilt virus (TSWV) infection of tomato plants by transcriptomic and hormones level analyses. In TSWV-infected mycorrhizal plants, the AM fungus root colonization limited virus-induced changes in gene expression in the aerial parts. The virus-responsive upregulated genes, no longer induced in infected mycorrhizal plants, were mainly involved in defense responses and hormone signaling, while the virus-responsive downregulated genes, no longer repressed in mycorrhizal plants, were involved in primary metabolism. The presence of the AM fungus limits, in a salicylic acid-independent manner, the accumulation of abscissic acid observed in response to viral infection. At the time of the molecular analysis, no differences in virus concentration or symptom severity were detected between mycorrhizal and nonmycorrhizal plants. However, in a longer period, increase in virus titer and delay in the appearance of recovery were observed in mycorrhizal plants, thus indicating that the plant's reaction to TSWV infection is attenuated by mycorrhization.
番茄（Solanum lycopersicum）可以与丛枝菌根（AM）真菌建立共生关系，并且可以被几种致病病毒感染。在这里，我们通过转录组学和激素水平分析研究了真菌摩西球囊霉（Glomus mosseae）的菌根化对番茄感染番茄斑点萎蔫病毒（TSWV）的影响。在感染 TSWV 的菌根植物中，AM 真菌的根系定殖限制了病毒诱导的地上部分基因表达的变化。不再诱导感染菌根植物中病毒响应的上调基因主要涉及防御反应和激素信号转导，而不再在菌根植物中被抑制的病毒响应下调基因则参与初级代谢。AM 真菌的存在以不依赖水杨酸的方式限制了病毒感染时观察到的脱落酸的积累。在分子分析时，未检测到菌根和非菌根植物之间病毒浓度或症状严重程度的差异。然而，在更长的时间内，菌根植物中的病毒滴度增加和恢复出现的延迟表明，菌根化减弱了植物对 TSWV 感染的反应。
