Liu Jinyuan, Yang Ruirui, Liang Yuqing, Wang Yan, Li Xiaoshuang
Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi, China.
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
Front Plant Sci. 2022 Apr 6;13:857396. doi: 10.3389/fpls.2022.857396. eCollection 2022.
Salinity is a major limiting factor in crop productivity. Dehydration-responsive element-binding protein (DREB) transcription factors have been widely identified in a variety of plants and play important roles in plant stress responses. Studies on DREBs have primarily focused on the A-1 and A-2 DREB groups, while few have focused on the A-5 group. In this study, we concentrated on , an A-5b type gene from the desiccation-tolerant moss . is a transcription factor localized to the nucleus that exhibits transactivation activity in yeast. Ectopic expression in increased seed germination and improved seedling tolerance under salt stress. -overexpression transgenic Arabidopsis lines showed lower methane dicarboxylic aldehyde (MDA) and hydrogen peroxide (HO) contents, but higher peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) activities compared to wild plants. Moreover, the transcriptional levels of stress marker genes, including , , , , , , and salt overly sensitive (SOS) genes (, , and ), were upregulated in the transgenic lines when subjected to salt treatment. Transcriptome and real-time quantitative PCR (RT-qPCR) analyses indicated that transgenic lines were accompanied by an increased expression of jasmonic acid (JA) biosynthesis genes, as well as a higher JA content under salt stress. Our results suggest that could improve salt tolerance by enhancing the scavenging abilities of reactive oxygen species (ROS), increasing JA content by upregulating JA synthesis gene expression, regulating ion homeostasis by up-regulating stress-related genes, osmotic adjustment, and protein protection, making a promising candidate gene for crop salt stress breeding.
盐度是作物生产力的主要限制因素。脱水响应元件结合蛋白（DREB）转录因子已在多种植物中被广泛鉴定，并在植物应激反应中发挥重要作用。对DREB的研究主要集中在A-1和A-2 DREB组，而对A-5组的研究较少。在本研究中，我们聚焦于来自耐旱苔藓的A-5b型基因。是一种定位于细胞核的转录因子，在酵母中表现出反式激活活性。在中的异位表达增加了种子萌发并提高了盐胁迫下幼苗的耐受性。与野生植物相比，过表达转基因拟南芥品系显示出较低的丙二醛（MDA）和过氧化氢（HO）含量，但具有较高过氧化物酶（POD）、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性。此外，在盐处理时，转基因品系中包括、、、、、和盐过度敏感（SOS）基因（、、）在内的应激标记基因的转录水平上调。转录组和实时定量PCR（RT-qPCR）分析表明，转基因品系在盐胁迫下伴随着茉莉酸（JA）生物合成基因表达的增加以及较高的JA含量。我们的结果表明，可通过增强活性氧（ROS）清除能力、上调JA合成基因表达来增加JA含量、上调应激相关基因来调节离子稳态、渗透调节和蛋白质保护来提高耐盐性，使成为作物盐胁迫育种的一个有前景的候选基因。
