“Fuji” is the predominant apple cultivar grown around the world, but it is highly susceptible to apple ring rot caused by . WRKY transcription factors (TFs) play key roles in multiple physiological responses to plant defense. We have previously reported the involvement of several MdWRKY TFs in plant defense against. In this study, we identified a new MdWRKY TF, , which is induced by infection. MdWRKY45 was localized in the nucleus and exhibited transcriptional activity. Over-expression of enhanced the resistance of transgenic apple calli and fruits to infection. Conversely, suppression of decreased the disease resistance of apple calli and fruits. Further transcriptome profiling and expression analysis showed that various genes regulating the release of salicylic acid (SA), jasmonic acid (JA), and reactive oxygen species (ROS) were either up-regulated or down-regulated in -RNAi transgenic apple calli compared with wild-type (WT). During infection, modulated the levels of SA and JA, as well as ROS burst. Moreover, MdWRKY45 could bind to the W-box cis-element in the promoters of and genes, thereby regulating their expression. In conclusion, primarily confers resistance to infection through pathways involving SA, JA, and ROS burst defense.

中文翻译：

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MdWRKY45 有助于苹果对 Botryosphaeria dothidea 的抗性

“富士”是世界各地种植的主要苹果品种，但它极易受到由 引起的苹果环腐病的影响。 WRKY 转录因子 (TF) 在植物防御的多种生理反应中发挥着关键作用。我们之前曾报道过几个 MdWRKY TF 参与植物防御。在这项研究中，我们鉴定了一种新的 MdWRKY TF，它是由感染诱导的。 MdWRKY45 定位于细胞核并表现出转录活性。过度表达增强了转基因苹果愈伤组织和果实对感染的抵抗力。相反，抑制会降低苹果愈伤组织和果实的抗病性。进一步的转录组分析和表达分析表明，与RNAi转基因苹果愈伤组织相比，调节水杨酸（SA）、茉莉酸（JA）和活性氧（ROS）释放的多种基因在-RNAi转基因苹果愈伤组织中上调或下调。野生型（WT）。在感染过程中，调节 SA 和 JA 的水平以及 ROS 的爆发。此外，MdWRKY45可以与基因启动子中的W盒顺式元件结合，从而调节其表达。总之，主要通过涉及 SA、JA 和 ROS 爆发防御的途径赋予对感染的抵抗力。