Zhao Jiahao, Zhang Shuhui, Yu Zhicheng, Gu Tingting, Zhang Jie, Meng Lingyu, Chen Zijing, Zhang Zongying, Wang Nan, Chen Xuesen, Liu Wenjun
College of Horticulture Science and Engineering, Shandong Agricultural University, Taian 271018, Shandong, China.
Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production, Taian 271018, Shandong, China.
Hortic Res. 2025 Mar 4;12(6):uhaf068. doi: 10.1093/hr/uhaf068. eCollection 2025 Jun.
Salt stress is an important abiotic stress affecting the growth and fruit quality of apple fruits. Although jasmonic acid (JA) hormones and WRKY transcription factors (TFs) have both been reported to be involved in plant salt stress responses, the molecular mechanisms by which JA-mediated WRKY TFs regulate salt stress in apples remain unclear. Here, we report the identification of a WRKY family TF from apple, MdWRKY9, and its involvement in apple salt tolerance by regulating the expression of Na/H antiporters, , and . Furthermore, we show that the protein repressors MdJAZ5 and MdJAZ10 in the JA signaling pathway can both interact with MdWRKY9 to form a complex and inhibit its DNA-binding and transcriptional activation activity. The JA signal triggers the degradation of MdJAZ5 and MdJAZ10 proteins by the 26S proteasome, disrupting the JAZ-WRKY protein complex and thereby releasing MdWRKY9 to activate downstream gene expression, promoting salt tolerance in apples. These findings provide important insights into the molecular mechanism of the WRKY TFs in JA-mediated salt tolerance in plants.
盐胁迫是影响苹果果实生长和果实品质的重要非生物胁迫。尽管茉莉酸（JA）激素和WRKY转录因子（TFs）均已被报道参与植物盐胁迫反应，但JA介导的WRKY TFs调控苹果盐胁迫的分子机制仍不清楚。在此，我们报道了从苹果中鉴定出一个WRKY家族TF，MdWRKY9，其通过调控Na/H逆向转运蛋白、和的表达参与苹果的耐盐性。此外，我们表明JA信号通路中的蛋白抑制因子MdJAZ5和MdJAZ10均可与MdWRKY9相互作用形成复合物，并抑制其DNA结合和转录激活活性。JA信号通过26S蛋白酶体触发MdJAZ5和MdJAZ10蛋白的降解，破坏JAZ-WRKY蛋白复合物，从而释放MdWRKY9以激活下游基因表达，促进苹果的耐盐性。这些发现为WRKY TFs在JA介导的植物耐盐性中的分子机制提供了重要见解。
