Soil salinization and alkalization are major problems in crop production. To gain insights into the mechanisms of saline-alkaline tolerance, we investigated the molecular response of a highly stress tolerant green alga, Nannochloris sp. JB17 (JB17) to NaHCO₃. Results indicated that JB17 cells retain a high level of cell viability when subjected to a high concentration (300 mM) of NaHCO₃. A transcriptome analyses was conducted of JB17 cells that were subjected to either 50 mM or 300 mM NaHCO₃ for 4 h, 24 h or 72 h. Thousands of differentially expressed genes (DEGs)¹ were identified, among which, 134 highly expressed DEGs were mainly enriched in photosynthesis-related processes. Gene co-expression analysis revealed the unique molecular profile of JB17 cells subjected to NaHCO₃ stress. Detailed analyses of the long-term and high concentration NaHCO₃ related modules indicated that the key pathways and hub genes were related to antioxidant capacity, carbohydrate metabolism, and cell division. Corresponding physiological experiments revealed that the antioxidant enzymes activity and the population of palmelloid cells significantly increased in JB17 cells under NaHCO₃ stress. Our data indicate that JB17 cells actively support photosynthesis and increase reactive oxygen species scavenging activity to survive in the presence of NaHCO₃. These results provide information on the regulatory mechanisms associated with saline-alkaline tolerance in Nannochloris.

土壤盐渍化和碱化是农作物生产中的主要问题。为了深入了解盐碱耐受性的机制，我们研究了高胁迫耐受性绿藻Nannochloris sp。的分子响应。JB17（JB17）至NaHCO ₃。结果表明，当经受高浓度（300 mM）的NaHCO ₃时，JB17细胞保持高水平的细胞活力。对JB17细胞进行转录组分析，将其分别置于50 mM或300 mM NaHCO _3中处理4 h，24 h或72 h。数千个差异表达基因（DEG）¹鉴定出，其中134个高表达DEG主要富集于光合作用相关过程。基因共表达分析揭示了受到NaHCO ₃胁迫的JB17细胞的独特分子特征。对长期和高浓度NaHCO ₃相关模块的详细分析表明，关键途径和中枢基因与抗氧化能力，碳水化合物代谢和细胞分裂有关。相应的生理实验表明，在NaHCO ₃下，JB17细胞的抗氧化酶活性和棕榈果细胞的数量显着增加。强调。我们的数据表明JB17细胞积极支持光合作用并增加活性氧清除能力，以在NaHCO ₃存在下存活。这些结果提供了与盐碱耐受性相关的调节机制信息小球藻。