Previous studies have indicated the potential role of a TIFY family gene, GsJAZ2, for its response to alkaline stress in Arabidopsis. Here, we transformed GsJAZ2 into an elite soybean (Glycine max) using particle bombardment-based genetic transformation system to assess whether overexpression of GsJAZ2 in soybean improved alkaline tolerance. Results revealed that transgenic soybean overexpressing GsJAZ2 grew well under alkaline conditions, while wild-type (WT) plants exhibited chlorosis, stunted growth, or even death. Higher chlorophyll concentration and lower of Malondialdehyde (MDA) content were detected in the transgenic plants compared to WT under alkaline stress. Moreover, the transcription levels of two alkaline-responsive genes were up-regulated in the GsJAZ2 overexpression at the early or later stage of alkaline stress, respectively, indicating that GsJAZ2 overexpression enhanced tolerance to alkaline stress in soybean, which might modulate intracellular pH homeostasis and osmotic balance through regulating the expression of alkaline-responsive genes. Additionally, GsJAZ2 is a member of the JAZ subfamily that belongs to the TIFY family. Overexpression of GsJAZ2 in soybean conferred JA insensitivity, including JA-mediated root growth inhibition. The transcripts of some JA-responsive genes were examined and altered under alkaline stress, implying that GsJAZ2 overexpression may involve in JA signal pathway for accumulating anti-osmotic substances in defense to alkaline stress. Collectively, the findings of this study facilitate our understanding of GsJAZ2 in response to alkaline stress as well as enrich the function of TIFY genes in crop.

先前的研究表明，TIFY家族基因GsJAZ2对于拟南芥中对碱胁迫的响应具有潜在的作用。在这里，我们使用基于粒子轰击的遗传转化系统将GsJAZ2转化为优质大豆（Glycine max），以评估GsJAZ2在大豆中的过表达是否提高了耐碱性。结果表明，转基因大豆过表达GsJAZ2在碱性条件下生长良好，而野生型（WT）植物表现出萎黄病，发育迟缓甚至死亡。与野生型相比，转基因植物在碱性胁迫下检测到较高的叶绿素浓度和较低的丙二醛（MDA）含量。此外，在碱性胁迫的早期或后期，GsJAZ2过表达中的两个碱性响应基因的转录水平分别上调，表明GsJAZ2过表达增强了大豆对碱性胁迫的耐受性，这可能调节细胞内pH稳态和通过调节碱性反应基因的表达实现渗透平衡。此外，GsJAZ2是TIFY家族的JAZ子家族的成员。大豆中GsJAZ2的过表达赋予JA不敏感性，包括JA介导的根生长抑制。在碱性胁迫下检查并改变了一些JA反应基因的转录本，这表明GsJAZ2的过表达可能参与了JA信号通路，从而积累了抗渗透物质以防御碱性胁迫。总的来说，这项研究的发现有助于我们理解GsJAZ2对碱性胁迫的反应，并丰富了作物中TIFY基因的功能。