Abstract：
Salt stress severely affects plant development and yield. Calcineurin B-like protein interacting protein kinases (CIPKs) play a crucial role in plant adaptation to environmental challenges. However, the biological functions of CIPKs in soybean remain poorly understood. Here, we identified GmCIPK21, a salt-responsive CIPK gene from soybean. Overexpression of GmCIPK21 in Arabidopsis and soybean hairy roots led to increased salt tolerance. The hairy roots with GmCIPK21 suppression by RNA interference exhibited salt-sensitive phenotypes. Further physiological analysis revealed that GmCIPK21 reduced the content of hydrogen peroxide (H2O2) and malondialdehyde (MDA) and increased the activity of the antioxidant enzymes under salt stress. Additionally, GmCIPK21 was found to enhance the ABA sensitivity of transgenic plants. GmCIPK21 was also implicated in increasing the activation of antioxidant-, salt-, and ABA-related genes upon salt stress. Interestingly, GmCIPK21 interacted with GmCBL4, promoting the scavenging salt-induced reactive oxygen species (ROS). These results collectively suggested that GmCIPK21 affects ROS homeostasis and ABA response to improve salt tolerance in soybean.
摘要：
盐胁迫严重影响植物发展和产量。钙调神经磷酸酶B样蛋白相互作用蛋白激酶（CIPK）在植物适应环境挑战中起着至关重要的作用。然而,大豆中CIPKs的生物学功能仍然知之甚少。这里,我们鉴定了GmCIPK21，一种来自大豆的盐反应性CIPK基因。GmCIPK21在拟南芥和大豆毛状根中的过表达导致耐盐性增加。通过RNA干扰抑制GmCIPK21的毛状根表现出盐敏感性表型。进一步的生理分析表明，在盐胁迫下，GmCIPK21降低了过氧化氢（H2O2）和丙二醛（MDA）的含量，并增加了抗氧化酶的活性。此外,发现GmCIPK21可增强转基因植物的ABA敏感性。GmCIPK21还涉及增加抗氧化剂的活化，盐-，和盐胁迫下的ABA相关基因。有趣的是,GmCIPK21与GmCBL4相互作用，促进清除盐诱导的活性氧（ROS）。这些结果共同表明GmCIPK21影响ROS稳态和ABA反应以提高大豆的耐盐性。
