Zhang Xiuming, Zhang Qihan, Zhu Yanxun, Zhang Yichu, Yan Xiaoxiao, Guo Chunlei, Gao Min, Li Zhi, Zhao Yijie, Lu Hua, Wang Xiping
State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture/College of Horticulture, Northwest A&F University, Yangling, China.
College of Enology and Horticulture, Ningxia University/College of Modern Grape and Wine Industry/Ningxia Grape and Wine Research Institute/Engineering Research Center of Grape and Wine, Ministry of Education, Yinchuan, China.
Plant Biotechnol J. 2025 Sep;23(9):3984-3999. doi: 10.1111/pbi.70196. Epub 2025 Jun 18.
Erysiphe necator, the causal agent of powdery mildew (PM), is a fungal pathogen that can severely reduce crop yields. In this study, stable overexpression and silencing demonstrated that the transcription factor VqWRKY46 was identified as a positive regulator of PM resistance in grapevine. This enhanced resistance was associated with increased callose deposition and hypersensitive response cell death. We also demonstrated that VqLIMYB specifically activated VqWRKY46 expression by binding to a CAGTTA motif in its promoter. Moreover, VqWRKY46 interacted with VqNF-YC9 and formed homodimers, positively regulating VqNF-YC9 expression by directly binding to three W-box motifs in its promoter. Additionally, DAP-Seq analysis identified VqDSC1, a TIR-NB-LRR resistance protein, as a downstream target of VqWRKY46 in grapevine. Further analysis indicated that VqWRKY46 directly bound to Wbox1 in the VqDSC1 promoter to upregulate its expression, whereas VqNF-YC9 did not bind. Interestingly, the interaction between VqNF-YC9 and VqWRKY46 enhanced the DNA binding activity of VqWRKY46 to promote the expression of VqDSC1. Furthermore, overexpressing VqLIMYB, VqNF-YC9, and VqDSC1 in Arabidopsis and/or instantaneous transformation in grapes showed that they are positive regulators of PM resistance. Collectively, our findings uncover a novel regulatory module (VqLIMYB-VqWRKY46/VqNF-YC9-VqDSC1) that mediates grapevine resistance to E. necator. This study provides new insights into the molecular basis of grapevine resistance to PM and highlights potential targets for breeding disease-resistant grapevines.
白粉菌（Erysiphe necator）是白粉病（PM）的病原体，是一种能严重降低作物产量的真菌病原体。在本研究中，稳定过表达和沉默表明转录因子VqWRKY46被鉴定为葡萄中抗白粉病的正调控因子。这种增强的抗性与胼胝质沉积增加和过敏反应性细胞死亡有关。我们还证明，VqLIMYB通过结合其启动子中的CAGTTA基序特异性激活VqWRKY46的表达。此外，VqWRKY46与VqNF-YC9相互作用并形成同源二聚体，通过直接结合其启动子中的三个W-box基序正向调控VqNF-YC9的表达。此外，DAP-Seq分析确定VqDSC1，一种TIR-NB-LRR抗性蛋白，是葡萄中VqWRKY46的下游靶标。进一步分析表明，VqWRKY46直接结合VqDSC1启动子中的Wbox1以上调其表达，而VqNF-YC9不结合。有趣的是，VqNF-YC9与VqWRKY46之间的相互作用增强了VqWRKY46的DNA结合活性，从而促进VqDSC1的表达。此外，在拟南芥中过表达VqLIMYB、VqNF-YC9和VqDSC1以及/或在葡萄中瞬时转化表明它们是抗白粉病的正调控因子。总体而言，我们的研究结果揭示了一个新的调控模块（VqLIMYB-VqWRKY46/VqNF-YC9-VqDSC1），该模块介导葡萄对白粉菌的抗性。本研究为葡萄对白粉病抗性的分子基础提供了新的见解，并突出了培育抗病葡萄的潜在靶点。
