Zhu Xi, Majeed Yasir, Duan Huimin, Zhang Ning, Wang Kaitong, Li Wei, Dou Xueting, Jin Hui, Chen Zhuo, Chen Shu, Tang Jinghua, Zhang Yu, Si Huaijun
Key Laboratory of Tropical Fruit Biology, Ministry of Agriculture and Rural Affairs/Key Laboratory of Hainan Province for Postharvest Physiology and Technology of Tropical Horticultural Products, South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, Guangdong, 524091, China; National Key Laboratory for Tropical Crop Breeding, Sanya Research Institute, Chinese Academy of Tropical Agricultural Sciences, Sanya, 572025, China.
State Key Laboratory of Aridland Crop Science, Gansu Agricultural University, Lanzhou, 730070, China; College of Agronomy, Gansu Agricultural University, Lanzhou, 730070, China.
Plant Physiol Biochem. 2025 Aug 5;229(Pt A):110342. doi: 10.1016/j.plaphy.2025.110342.
Potato (Solanum tuberosum L.), a staple crop, is highly susceptible to environmental stressors such as high salinity and elevated temperatures. Calcineurin B-like (CBL) proteins and CBL-interacting protein kinases (CIPKs) form sensor-response complexes that regulate plant growth, development, differentiation, and stress responses. In this study, the differential expression of 14 StCBL genes and 27 StCIPK genes under salt and heat stress conditions was assessed by quantitative real-time PCR (qRT-PCR). Our experimental findings demonstrated that the salt and heat stressors significantly induced the upregulation of StCIPK15 at specific time points. Laser confocal microscopy revealed that the StCIPK15-EGFP fusion protein localized to the membrane and nucleus. Interactions between StCIPK15 and specific StCBL proteins (StCBL1, StCBL2, StCBL4, StCBL6, and StCBL9) were confirmed using yeast two-hybrid (Y2H) assays. These interactions were further validated through bimolecular fluorescence complementation (BiFC) assays. Transgenic potato plants overexpressing StCIPK15 (OE-1, OE-2, and OE-6) and StCIPK15 knockdown plants (Ri-2, Ri-4, and Ri-5) were generated. Phenotypic analysis revealed significant differences in growth parameters, such as plant height and biomass, between transgenic and non-transgenic (NT) potato plants under NaCl and high-temperature stresses. Overexpression of StCIPK15 enhanced physiological resilience. This was evidenced by elevated proline content, upregulated StP5CS expression, boosted SOD/CAT/POD activities and transcripts of StSOD/StCAT/StPOD, alongside reduced relative conductivity, HO/MDA accumulation, and ProDH1 expression. Conversely, StCIPK15 knockdown plants showed the opposite outcomes. Furthermore, transgenic potato plants demonstrated notable enhancements in photosynthetic efficiency, including higher net photosynthetic rates, increased stomatal conductance, elevated transpiration rates, and improved water-use efficiency relative to non-transgenic lines, which indicates that StCIPK15 enhances photosynthetic efficiency. Overall, these findings enhance our knowledge of the biological mechanisms that determine how StCIPK15 regulates salt and heat tolerance in potato plants.
马铃薯（Solanum tuberosum L.）是一种主食作物，极易受到高盐度和高温等环境胁迫因素的影响。类钙调神经磷酸酶B（CBL）蛋白和CBL相互作用蛋白激酶（CIPK）形成传感-反应复合物，调节植物的生长、发育、分化和胁迫反应。在本研究中，通过定量实时PCR（qRT-PCR）评估了14个StCBL基因和27个StCIPK基因在盐胁迫和热胁迫条件下的差异表达。我们的实验结果表明，盐胁迫和热胁迫在特定时间点显著诱导了StCIPK15的上调。激光共聚焦显微镜显示，StCIPK15-EGFP融合蛋白定位于细胞膜和细胞核。使用酵母双杂交（Y2H）试验证实了StCIPK15与特定的StCBL蛋白（StCBL1、StCBL2、StCBL4、StCBL6和StCBL9）之间的相互作用。通过双分子荧光互补（BiFC）试验进一步验证了这些相互作用。构建了过表达StCIPK15的转基因马铃薯植株（OE-1、OE-2和OE-6）和StCIPK15基因沉默植株（Ri-2、Ri-4和Ri-5）。表型分析表明，在NaCl和高温胁迫下，转基因马铃薯植株与非转基因（NT）马铃薯植株在株高和生物量等生长参数上存在显著差异。StCIPK15的过表达增强了生理恢复力。这表现为脯氨酸含量升高、StP5CS表达上调、SOD/CAT/POD活性增强以及StSOD/StCAT/StPOD转录本增加，同时相对电导率降低、HO/MDA积累减少以及ProDH1表达降低。相反，StCIPK15基因沉默植株表现出相反的结果。此外，与非转基因品系相比，转基因马铃薯植株的光合效率显著提高，包括更高的净光合速率、增加的气孔导度、升高的蒸腾速率和提高的水分利用效率，这表明StCIPK15提高了光合效率。总体而言，这些发现增进了我们对决定StCIPK15如何调节马铃薯植株耐盐性和耐热性的生物学机制的了解。
