Department of Biotechnology, Panjab University, BMS Block I, Sector 25, Chandigarh, -160014, India.
National Research Centre for Grapes, Solapur Road, Pune, Maharashtra, 412 307, India.
BMC Genomics. 2021 Oct 30;22(1):776. doi: 10.1186/s12864-021-08081-4.
Grapevine (Vitis vinifera) productivity has been severely affected by various bacterial, viral and fungal diseases worldwide. When a plant is infected with the pathogen, various defense mechanisms are subsequently activated in plants at various molecular levels. Thus, for substantiating the disease control in an eco-friendly way, it is essential to understand the molecular mechanisms governing pathogen resistance in grapes.
In our study, we performed genome-wide identification of various defensive genes expressed during powdery mildew (PM) and downy mildew (DM) infections in grapevine. Consequently, we identified 6, 21, 2, 5, 3 and 48 genes of Enhanced Disease Susceptibility 1 (EDS1), Non-Race-specific Disease Resistance (NDR1), Phytoalexin deficient 4 (PAD4), Nonexpressor of PR Gene (NPR), Required for Mla-specified resistance (RAR) and Pathogenesis Related (PR), respectively, in the grapevine genome. The phylogenetic study revealed that V. vinifera defensive genes are evolutionarily related to Arabidopsis thaliana. Differential expression analysis resulted in identification of 2, 4, 7, 2, 4, 1 and 7 differentially expressed Nucleotide-binding leucine rich repeat receptor (NLR), EDS1, NDR1, PAD4, NPR, RAR1 and PR respectively against PM infections and 28, 2, 5, 4, 1 and 19 differentially expressed NLR, EDS1, NDR1, NPR, RAR1 and PR respectively against DM infections in V. vinifera. The co-expression study showed the occurrence of closely correlated defensive genes that were expressed during PM and DM stress conditions.
The PM and DM responsive defensive genes found in this study can be characterized in future for impelling studies relaying fungal and oomycete resistance in plants, and the functionally validated genes would then be available for conducting in-planta transgenic gene expression studies for grapes.
葡萄藤的生产力受到世界各地各种细菌、病毒和真菌病害的严重影响。当植物感染病原体时，植物在不同分子水平上会激活各种防御机制。因此，为了以生态友好的方式证实疾病的控制，了解控制葡萄病原体抗性的分子机制是至关重要的。
在我们的研究中，我们对葡萄藤在白粉病和霜霉病感染过程中表达的各种防御基因进行了全基因组鉴定。结果，我们分别在葡萄基因组中鉴定出 6、21、2、5、3 和 48 个增强疾病易感性 1（EDS1）、非专化性疾病抗性（NDR1）、缺植保素 4（PAD4）、非表达 PR 基因（NPR）、Mla 特异性抗性所需（RAR）和与病程相关（PR）的基因。系统发育研究表明，V.vinifera 防御基因与拟南芥在进化上是相关的。差异表达分析结果表明，针对白粉病感染，有 2、4、7、2、4、1 和 7 个差异表达核苷酸结合富含亮氨酸重复受体（NLR）、EDS1、NDR1、PAD4、NPR、RAR1 和 PR，而针对霜霉病感染，有 28、2、5、4、1 和 19 个差异表达 NLR、EDS1、NDR1、NPR、RAR1 和 PR。共表达研究表明，在白粉病和霜霉病胁迫条件下，发生了密切相关的防御基因表达。
本研究中发现的白粉病和霜霉病响应防御基因可进一步表征，以促进植物对真菌和卵菌抗性的研究，功能验证的基因可用于葡萄的体内转基因基因表达研究。
