Peng Yuquan, Cui Lvjun, Wang Ying, Wei Lanxing, Geng Shouyu, Chen Hui, Chen Guoyu, Yang Li, Bie Zhilong
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops/College of Horticulture and Forestry Sciences, Huazhong Agricultural University, 430070 Wuhan, China.
Hubei Hongshan Laboratory, Department of Science and Technology of Hubei Province, 430070 Wuhan, China.
Hortic Res. 2024 Feb 28;11(5):uhae057. doi: 10.1093/hr/uhae057. eCollection 2024 May.
Pumpkin CmoNAC1 enhances salt tolerance in grafted cucumbers. However, the potential interactions with other proteins that may co-regulate salt tolerance alongside CmoNAC1 have yet to be explored. In this study, we identified pumpkin CmoDREB2A as a pivotal transcription factor that interacts synergistically with CmoNAC1 in the co-regulation of salt tolerance. Both transcription factors were observed to bind to each other's promoters, forming a positive regulatory loop of their transcription. Knockout of in the root resulted in reduced salt tolerance in grafted cucumbers, whereas overexpression demonstrated the opposite effect. Multiple assays in our study provided evidence of the protein interaction between CmoDREB2A and CmoNAC1. Exploiting this interaction, CmoDREB2A facilitated the binding of CmoNAC1 to the promoters of , , , and , inducing HO and ABA synthesis and increasing the K/Na ratio in grafted cucumbers under salt stress. Additionally, CmoNAC1 also promoted the binding of CmoDREB2A to / promoters, further contributing to the K/Na homeostasis. In summary, these findings reveal a crucial mechanism of CmoNAC1 and CmoDREB2A forming a complex enhancing salt tolerance in grafted cucumbers.
南瓜CmoNAC1增强嫁接黄瓜的耐盐性。然而，与可能与CmoNAC1共同调节耐盐性的其他蛋白质之间的潜在相互作用尚未得到探索。在本研究中，我们鉴定出南瓜CmoDREB2A是一种关键转录因子，它在耐盐性的共同调节中与CmoNAC1协同相互作用。观察到这两种转录因子相互结合对方的启动子，形成它们转录的正调控环。敲除根部的 导致嫁接黄瓜的耐盐性降低，而过表达则表现出相反的效果。我们研究中的多项试验提供了CmoDREB2A与CmoNAC1之间蛋白质相互作用的证据。利用这种相互作用，CmoDREB2A促进CmoNAC1与 、 、 和 的启动子结合，在盐胁迫下诱导HO和ABA合成并增加嫁接黄瓜中的K/Na比率。此外，CmoNAC1还促进CmoDREB2A与 / 启动子的结合，进一步有助于K/Na稳态。总之，这些发现揭示了CmoNAC1和CmoDREB2A形成复合物增强嫁接黄瓜耐盐性的关键机制。
