Biotechnology and Germplasm Resources Research Institute, Yunnan Academy of Agricultural Sciences, 2238# Beijing Rd., Panlong District, Kunming 650205, China.
Deputy Director of Microbiology Laboratory, Department of Biotechnology Research, Ministry of Science and Technology, Tansoe Rd., Kyaukse 05151, Myanmar.
Int J Mol Sci. 2024 Oct 10;25(20):10907. doi: 10.3390/ijms252010907.
The plant vascular system is not only a transportation system for delivering nutrients but also a highway transport network for spreading viruses. Tomato spotted wilt orthotospovirus (TSWV) is among the most destructive viruses that cause serious losses in economically important crops worldwide. However, there is minimal information about the long-distance movements of TSWV in the host plant vascular system. In this this study, we confirm that TSWV virions are present in the xylem as observed by transmission electron microscopy (TEM). Further, a quantitative proteomic analysis based on label-free methods was conducted to reveal the uniqueness of protein expression in xylem sap during TSWV infection. Thus, this study identified and quantified 3305 proteins in two groups. Furthermore, TSWV infection induced three viral structural proteins, N, Gn and Gc, and 315 host proteins differentially expressed in xylem (163 up-regulated and 152 down-regulated). GO enrichment analysis showed up-regulated proteins significantly enriched in homeostasis, wounding, defense response, and DNA integration terms, while down-regulated proteins significantly enriched in cell wall biogenesis/xyloglucan metabolic process-related terms. KEGG enrichment analysis showed that the differentially expressed proteins (DEPs) were most strongly associated with plant-pathogen interaction, MAPK signaling pathway, and plant hormone signal transduction. Cluster analysis of DEPs function showed the DEPs can be categorized into cell wall metabolism-related proteins, antioxidant proteins, PCD-related proteins, host defense proteins such as receptor-like kinases (RLKs), salicylic acid binding protein (SABP), pathogenesis related proteins (PR), DNA methylation, and proteinase inhibitor (PI). Finally, parallel reaction monitoring (PRM) validated 20 DEPs, demonstrating that the protein abundances were consistent between label-free and PRM data. Finally, 11 genes were selected for RT-qPCR validation of the DEPs and label-free-based proteomic analysis concordant results. Our results contribute to existing knowledge on the complexity of host plant xylem system response to virus infection and provide a basis for further study of the mechanism underlying TSWV long-distance movement in host plant vascular system.
植物维管束系统不仅是输送养分的运输系统，也是传播病毒的高速公路运输网络。番茄斑萎病毒（TSWV）是最具破坏性的病毒之一，它会导致全球经济作物的严重损失。然而，关于 TSWV 在宿主植物维管束系统中的长距离运动，信息很少。在这项研究中，我们通过透射电子显微镜（TEM）证实 TSWV 病毒粒子存在于木质部中。此外，我们还进行了基于无标记方法的定量蛋白质组学分析，以揭示 TSWV 感染时木质部汁液中蛋白质表达的独特性。因此，本研究在两组中鉴定和定量了 3305 种蛋白质。此外，TSWV 感染诱导了三种病毒结构蛋白 N、Gn 和 Gc，以及 315 种在木质部中差异表达的宿主蛋白（163 种上调和 152 种下调）。GO 富集分析显示，上调蛋白显著富集于内稳态、创伤、防御反应和 DNA 整合等术语，而下调蛋白则显著富集于细胞壁生物发生/木葡聚糖代谢过程相关术语。KEGG 富集分析表明，差异表达蛋白（DEPs）与植物-病原体相互作用、MAPK 信号通路和植物激素信号转导关系最密切。DEPs 功能聚类分析表明，DEPs 可分为细胞壁代谢相关蛋白、抗氧化蛋白、PCD 相关蛋白、类受体激酶（RLKs）、水杨酸结合蛋白（SABP）、病程相关蛋白（PR）、DNA 甲基化和蛋白酶抑制剂（PI）等。最后，平行反应监测（PRM）验证了 20 个 DEPs，表明无标记和 PRM 数据之间的蛋白丰度一致。最后，选择了 11 个基因进行 RT-qPCR 验证 DEPs 和无标记基础蛋白质组学分析的一致性结果。我们的研究结果丰富了宿主植物木质部系统对病毒感染反应复杂性的现有知识，并为进一步研究 TSWV 在宿主植物维管束系统中的长距离运动机制提供了依据。
