Philosoph Amit M, Dombrovsky Aviv, Luria Neta, Sela Noa, Elad Yigal, Frenkel Omer
Department of Plant Pathology and Weed Science, The Volcani Institute, Agricultural Research Organization, Bet Dagan, Israel.
The Robert H. Smith Faculty of Agriculture, Food and Environment, The Levi Eshkol School of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel.
Front Plant Sci. 2023 Jun 9;14:1124911. doi: 10.3389/fpls.2023.1124911. eCollection 2023.
Combined infection of the host plant with pathogens involving different parasitic lifestyles may result in synergistic effects that intensify disease symptoms. Understanding the molecular dynamics during concurrent infection provides essential insight into the host response. The transcriptomic pattern of cucumber plants infected with a necrotrophic pathogen, , and a biotrophic pathogen, Cucumber green mottle mosaic virus (CGMMV) was studied at different time points, under regimes of single and co-infection. Analysis of CGMMV infection alone revealed a mild influence on host gene expression at the stem base, while the infection by is associated with drastic changes in gene expression. Comparing as a single infecting pathogen with a later co-infection by CGMMV revealed a rapid host response as early as 24 hours post-CGMMV inoculation with a sharp downregulation of genes related to the host defense mechanism against the necrotrophic pathogen. Suppression of the defense mechanism of co-infected plants was followed by severe stress, including 30% plants mortality and an increase of the hyphae. The first evidence of defense recovery against the necrotrophic pathogen only occurred 13 days post-viral infection. These results support the hypothesis that the viral infection of the Pythium pre-infected plants subverted the host defense system and changed the equilibrium obtained with . It also implies a time window in which the plants are most susceptible to after CGMMV infection.
宿主植物被涉及不同寄生生活方式的病原体联合感染可能会导致协同效应，从而加剧疾病症状。了解同时感染期间的分子动态有助于深入了解宿主的反应。在单感染和共感染情况下，研究了感染坏死营养型病原体和活体营养型病原体黄瓜绿斑驳花叶病毒（CGMMV）的黄瓜植株在不同时间点的转录组模式。单独分析CGMMV感染发现其对茎基部的宿主基因表达影响较小，而感染则与基因表达的剧烈变化有关。将作为单一感染病原体与随后被CGMMV共感染进行比较，发现在接种CGMMV后24小时宿主就出现了快速反应，与宿主针对坏死营养型病原体的防御机制相关的基因急剧下调。共感染植物的防御机制受到抑制后，会出现严重胁迫，包括30%的植物死亡以及菌丝增加。对坏死营养型病原体的防御恢复的首个证据直到病毒感染后13天才出现。这些结果支持了以下假设：预先感染腐霉菌的植物被病毒感染后颠覆了宿主防御系统，并改变了与之间达成的平衡。这也意味着在CGMMV感染后，植物对最易感的一个时间窗口。
