Liu Wandi, Yan Chaohui, Li Ruimin, Liu Guotian, Wang Yuejin
College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China; State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi 712100. China; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China; State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi 712100. China; Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
Plant Sci. 2025 Oct;359:112607. doi: 10.1016/j.plantsci.2025.112607. Epub 2025 Jun 18.
Previously, we identified five stilbene synthase family members, VqNSTS2-VqNSTS6, from Chinese wild grapevine (Vitis quinquangularis) accession 'Danfeng-2' using transcriptome analysis. Promoter sequence analysis revealed that the promoters of all the VqNSTS genes harbor GT transcription factor (TF) binding motifs. Gene correlation analysis revealed a robust relationship between VqGT33 and VqNSTS6. Yeast one hybrid (Y1H) and dual luciferase (DLR) assays confirmed the binding of VqGT33 to VqNSTS2-VqNSTS6 promoters. Further investigation indicated that VqGT33 specifically binds to the GT-box2, GT-box3, and GT-box4 motifs, but not to GT-box1. In comparison to the VvGT33 promoter, we observed both deletion and insertion mutations in the VqGT33 promoter. GUS activity driven by the VqGT33 promoter significantly increased upon inoculation with Erysiphe necator and salicylic acid (SA) compared to the control, while no significant change was observed with the VvGT33 promoter post-infection, suggesting a pathogen-responsive nature of the VqGT33 promoter. Transient overexpression of VqGT33 in leaves enhanced stilbene and SA accumulation after E. necator inoculation, leading to increased resistance. Overexpression of VqGT33 also upregulated VqNSTSs and the disease-resistance genes VqPR1, VqPR5, VqRBOHD, and VqCHIT4C post-infection. Conversely, RNAi silencing of VqGT33 had contrasting effects. These findings suggest that VqGT33 plays a role in responding to powdery mildew (PM), by regulating the expression of VqNSTSs, promoting stilbene accumulation, and enhancing resistance to PM.
此前，我们通过转录组分析从中国野生葡萄（刺葡萄‘丹凤 - 2’）中鉴定出五个芪合酶家族成员，即VqNSTS2 - VqNSTS6。启动子序列分析表明，所有VqNSTS基因的启动子都含有GT转录因子（TF）结合基序。基因相关性分析揭示了VqGT33与VqNSTS6之间存在紧密关系。酵母单杂交（Y1H）和双荧光素酶（DLR）分析证实了VqGT33与VqNSTS2 - VqNSTS6启动子的结合。进一步研究表明，VqGT33特异性结合GT - box2、GT - box3和GT - box4基序，但不结合GT - box1。与VvGT33启动子相比，我们在VqGT33启动子中观察到缺失和插入突变。与对照相比，接种葡萄白粉菌和水杨酸（SA）后，由VqGT33启动子驱动的GUS活性显著增加，而感染后VvGT33启动子未观察到显著变化，这表明VqGT33启动子具有病原体响应特性。在叶片中瞬时过表达VqGT33可增强接种葡萄白粉菌后芪和SA的积累，从而提高抗性。感染后，VqGT33的过表达还上调了VqNSTSs以及抗病基因VqPR1、VqPR5、VqRBOHD和VqCHIT4C。相反，VqGT33的RNAi沉默则产生相反的效果。这些发现表明，VqGT33通过调节VqNSTSs的表达、促进芪的积累以及增强对白粉病的抗性，在对白粉病（PM）的响应中发挥作用。
