Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009, China.
National Key Facilities for Crop Genetic Resources and Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Plant Mol Biol. 2021 Feb;105(3):333-345. doi: 10.1007/s11103-020-01091-y. Epub 2020 Nov 5.
We found GmNAC06 plays an important role in salt stress responses through the phenotypic, physiological and molecular analyses of OE, VC, and Mutant composite soybean. Salinization affects 20% of all cultivated land worldwide because of the high salinity of irrigation water and the excessive use of water, and this amount is increasing daily. NAC (NAM, ATAF, and CUC) have been found to be involved in salt stress. In this study, a soybean NAC gene, GmNAC06 (Glyma06g21020.1), was cloned and functionally characterized. The results of expression analysis suggested that salt stress could influence the expression level of GmNAC06. The subcellular localization analysis results suggested that GmNAC06 may function as a transcription factor. Under salt stress, the overexpression technology combined with CRISPR-Cas9 system found that GmNAC06 could cause the accumulation of proline and glycine betaine to alleviate or avoid the negative effects of ROS; similarly, it could control the Na/K ratios in hairy roots to maintain ionic homeostasis. The fresh weight of the transgenic hairy roots and the histochemical ROS staining of wild leaves suggested that transgenic hairy roots influence the function of wild leaves under salt stress conditions. Moreover, the expression levels of GmUBC2 and GmHKT1 were higher in the GmNAC06 hairy roots than in the control. Thus, the overexpression of GmNAC06 in hairy roots notably causes an entire composite plant to exhibit salt tolerance. The phenotype of composite soybean plants and transgenic Arabidopsis plants suggest that GmNAC06 plays a role in response to salt stress and could be useful in generating salt tolerant transgenic crops.
我们发现 GmNAC06 通过对过表达（OE）、VC 和突变体复合大豆的表型、生理和分子分析，在盐胁迫反应中发挥重要作用。由于灌溉水的高盐度和过度用水，全球 20%的耕地受到盐化的影响，而且这一数字还在每天增加。已经发现 NAC（NAM、ATAF 和 CUC）参与了盐胁迫。在这项研究中，克隆并功能表征了大豆 NAC 基因 GmNAC06（Glyma06g21020.1）。表达分析结果表明，盐胁迫会影响 GmNAC06 的表达水平。亚细胞定位分析结果表明，GmNAC06 可能作为转录因子发挥作用。在盐胁迫下，过表达技术与 CRISPR-Cas9 系统结合发现，GmNAC06 可以导致脯氨酸和甘氨酸甜菜碱的积累，从而缓解或避免 ROS 的负面影响；同样，它可以控制毛状根中的 Na/K 比值，以维持离子平衡。转基因毛状根的鲜重和野生叶片的组织化学 ROS 染色表明，在盐胁迫条件下，转基因毛状根影响野生叶片的功能。此外，GmNAC06 毛状根中的 GmUBC2 和 GmHKT1 的表达水平高于对照。因此，GmNAC06 在毛状根中的过表达显著导致整个复合植物表现出耐盐性。复合大豆植株和转基因拟南芥植株的表型表明，GmNAC06 在响应盐胁迫中发挥作用，并可用于生成耐盐转基因作物。
