Overexpression of S-adenosyl-L-methionine synthetase increased tomato tolerance to alkali stress through polyamine metabolism
Overexpression of S-adenosyl-L-methionine synthetase increased tomato tolerance to alkali stress through polyamine metabolism
复制标题
S-腺苷-L-甲硫氨酸合成酶的过度表达通过多胺代谢增强番茄对碱胁迫的耐受性
DOI：
10.1111/pbi.12173
复制
发表时间：
2014-08-01
影响因子：
13.8
通讯作者：
Wang, Xiufeng
中科院分区：
文献类型：
--
作者：
Gong, Biao;Li, Xiu;Wang, Xiufeng
腺苷甲硫氨酸合成酶是腺苷甲硫氨酸生物合成的关键酶，是多胺和乙烯的共同前体。使用根癌农杆菌转化方法将SAM合成酶cDNA（SlSAMS 1）导入番茄基因组中。与WT株系相比，过表达SlSAMS 1的转基因植株表现出对碱胁迫的耐受性显著提高，并保持了养分平衡，具有较高的光合能力和较低的氧化胁迫。体内和离体实验均表明，SlSAMS 1的功能主要依赖于Spd和Spm在转基因株系中的积累。嫁接实验表明，从SlSAMS 1-过表达植物的砧木提供了一个更强大的根系，增加PAs积累，必需元素的吸收，减少Na+吸收的接穗在碱胁迫下。结果表明，坐果率和产量显著提高。据我们所知，这是第一份报告，提供证据表明，SlSAMS 1积极调节番茄耐碱性胁迫，并在调节多胺代谢中发挥重要作用，从而维持营养和活性氧平衡。
S-adenosyl-L-methionine (SAM) synthetase is the key enzyme involved in the biosynthesis of SAM, which serves as a common precursor for polyamines (PAs) and ethylene. A SAM synthetase cDNA (SlSAMS1) was introduced into the tomato genome using the Agrobacterium tumefaciens transformation method. Transgenic plants overexpressing SlSAMS1 exhibited a significant increase in tolerance to alkali stress and maintained nutrient balance, higher photosynthetic capacity and lower oxidative stress compared with WT lines. Both in vivo and in vitro experiments indicated that the function of SlSAMS1 mainly depended on the accumulation of Spd and Spm in the transgenic lines. A grafting experiment showed that rootstocks from SlSAMS1-overexpressing plants provided a stronger root system, increased PAs accumulation, essential elements absorption, and decreased Na+ absorption in the scions under alkali stress. As a result, fruit set and yield were significantly enhanced. To our knowledge, this is the first report to provide evidence that SlSAMS1 positively regulates tomato tolerance to alkali stress and plays a major role in modulating polyamine metabolism, resulting in maintainability of nutrient and ROS balance.