Li Caiyue, Zhang Qiang, Wang Xuebo, Liu Zhengwen, Zhang Xinyao, Jiang Caihong, Cheng Lirui, Yang Aiguo, Li Yangyang, Ji Yan, Liu Dan
Key Laboratory for Tobacco Gene Resources, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101, China.
Tobacco Research Institute of Shaanxi, Xi'an, 710077, China.
BMC Plant Biol. 2025 Aug 6;25(1):1029. doi: 10.1186/s12870-025-07053-0.
Tobacco mosaic virus (TMV) severely impairs plant growth, leading to significant economic losses in the production of various Solanaceae crops, including tobacco (Nicotiana tabacum), tomato (Solanum lycopersicum) and pepper (Caspicum annuum). To investigate TMV resistance mechanisms, we analyzed the transcriptomic and metabolomic profiles of susceptible (K326) and resistant (R_K326) tobacco lines. Transcriptomic analysis revealed that the number of differentially expressed genes (DEGs) in R_K326 was about 2 times higher than in K326 at 9 days post-inoculation (dpi), suggesting a greater involvement of defense-related genes in the resistant line. KEGG pathway analysis of DEGs highlighted the significant enrichment of biotic-stress related pathways that were specifically activated in R_K326 line following TMV infection. Notably, the flavonoid biosynthesis pathway was enriched in both transcriptomic and metabolomic analyses of R_K326. At 9 dpi, four flavonoid compounds accumulated at significantly higher levels in R_K326 compared to K326. Among them, naringin was demonstrated as a key player in TMV resistance by exogenous treatment and western blot analysis of TMV coat proteins. Two genes encoding the rate-limiting enzymes of naringin biosynthesis, asm_5.4770 and asm_7.408, were screened as candidate genes according to their high expression levels in R_K326. Additionally, Salicylic acid (SA) biosynthesis-related genes were up-regulated in R_K326, accompanied by the significant accumulation of SA levels. These results suggest that both the naringin and SA positively regulate tobacco resistance to TMV, providing insights into the response mechanisms of tobacco to TMV infection and new targets for TMV resistance breeding in Solanaceae crops.
烟草花叶病毒（TMV）严重损害植物生长，导致包括烟草（烟草）、番茄（番茄）和辣椒（辣椒）在内的各种茄科作物生产遭受重大经济损失。为了研究TMV抗性机制，我们分析了易感（K326）和抗性（R_K326）烟草品系的转录组和代谢组谱。转录组分析显示，接种后9天（dpi），R_K326中差异表达基因（DEG）的数量比K326中高出约2倍，这表明抗性品系中与防御相关的基因参与程度更高。对DEG进行的KEGG通路分析突出了生物胁迫相关通路的显著富集，这些通路在TMV感染后的R_K326品系中被特异性激活。值得注意的是，在R_K326的转录组和代谢组分析中，类黄酮生物合成途径均得到富集。在9 dpi时，与K326相比，R_K326中有四种类黄酮化合物积累水平显著更高。其中，柚皮苷通过外源处理和TMV外壳蛋白的蛋白质印迹分析被证明是TMV抗性的关键因素。根据它们在R_K326中的高表达水平，筛选出两个编码柚皮苷生物合成限速酶的基因asm_5.4770和asm_7.408作为候选基因。此外，水杨酸（SA）生物合成相关基因在R_K326中上调，同时SA水平显著积累。这些结果表明，柚皮苷和SA均正向调节烟草对TMV的抗性，为烟草对TMV感染反应机制及茄科作物TMV抗性育种新靶点提供了见解。
