Li Chunhong, Cao Shifeng, Wang Kaituo, Lei Changyi, Ji Nana, Xu Feng, Jiang Yongbo, Qiu Linglan, Zheng Yonghua
College of Life and Food Engineering, Chongqing Three Gorges University, Chongqing, China.
College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China.
Front Plant Sci. 2021 Mar 8;12:646147. doi: 10.3389/fpls.2021.646147. eCollection 2021.
Although heat shock proteins (HSPs), a family of ubiquitous molecular chaperones, are well characterized in heat stress-related responses, their function in plant defense remains largely unclear. Here, we report the role of , a class B HSP from , in β-aminobutyric acid (BABA)-induced priming defense against the necrotrophic fungus in grapes. Grapes treated with 10 mmol L BABA exhibited transiently increased transcript levels of and several SA-inducible genes, including , , and . Additionally, phytoalexins accumulated upon inoculation with the gray mold fungus , which coincided with the action of a priming mode implicated in pathogen-driven resistance. Intriguingly, electrophoretic mobility shift (EMSA), yeast two-hybrid (Y2H) and His pull-down assays demonstrated that the nuclear chaperone cannot modulate the transcript of genes but does directly interact with or . Furthermore, we found that overexpression enhanced the transcript levels of NPR1 and SA-responsive genes (, , and ) and increased the resistance of transgenic to compared with wildtype Col-0. An opposite trend between CRISPR mutants of (the orthologous gene of in ) and wildtype plants was observed. Hence, our results suggest that has a potential role in NPR1-dependent plant resistance to fungal pathogen. BABA-induced priming defense in grapes may require posttranslational modification of the chaperone to activate transcript, leading to gene expressions and resistance phenotypes.
尽管热休克蛋白（HSPs）作为一类普遍存在的分子伴侣，在热应激相关反应中已得到充分表征，但其在植物防御中的功能仍 largely 不清楚。在这里，我们报道了来自 的 B 类热休克蛋白 在葡萄中 β-氨基丁酸（BABA）诱导的对坏死性真菌 的引发防御中的作用。用 10 mmol/L BABA 处理的葡萄表现出 以及几个 SA 诱导基因（包括 、 和 ）的转录水平短暂升高。此外，接种灰霉病菌后植物抗毒素积累，这与病原体驱动抗性中涉及的引发模式的作用一致。有趣的是，电泳迁移率变动分析（EMSA）、酵母双杂交（Y2H）和 His 下拉分析表明，核伴侣 不能调节 基因的转录，但确实直接与 或 相互作用。此外，我们发现 过表达增强了 NPR1 和 SA 响应基因（ 、 和 ）的转录水平，并与野生型 Col-0 相比增加了转基因 对 的抗性。在 （ 中的直系同源基因）的 CRISPR 突变体和野生型植物之间观察到相反的趋势。因此，我们的结果表明 在 NPR1 依赖的植物对真菌病原体的抗性中具有潜在作用。BABA 诱导的葡萄引发防御可能需要伴侣 的翻译后修饰来激活 转录，从而导致 基因表达和抗性表型。
