We investigated the effect of overexpressing Fragaria vesca L. cv. Rügen S-adenosyl-l-methionine synthase (FvSAMS) and decarboxylase (FvSAMDC) genes on control and salt stressed Nicotiana benthamiana Domin plants. According to previous studies the overproduction of both proteins enhances the abiotic stress tolerance of plants, but the two enzymes have not yet been studied in one experimental system. We found that the transgenic plants subjected to long-term salt stress displayed higher levels of tolerance than the wild type (WT). In contrast to several earlier studies no antagonistic effect between ethylene and polyamine biosynthesis was observed in our experimental system. Overexpression of FvSAMDC had higher impact on the plant physiological parameters both in control and salt stress conditions, than that of FvSAMS. Based on the data measured in the FvSAMDC lines there appears to be a positive correlation between the free polyamine levels and the proline content as well as the amount of ethylene, while there is a negative correlation between the free polyamine levels and the lignin content in the plants exposed to salt stress. The transformation vectors contained the CaMV35S promoter, the coding sequence of FvSAMS and FvSAMDC fused with synthetic green fluorescent protein (sGFP). We detected the subcellular localization of both enzymes and examined the possible stress induced changes in their distribution. In the case of FvSAMS::sGFP nuclear, nucleolar, cytoplasmic (near to the plasmalemma), plastid membrane, whereas in FvSAMDC::sGFP nuclear and homogenous cytoplasmic localization was detected. Therefore, SAM is assumed to be produced in situ for numerous biochemical reactions.

中文翻译：

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转基因本氏烟草在盐胁迫下过表达草莓 S-腺苷-l-甲硫氨酸合酶 (FvSAMS) 和脱羧酶 (FvSAMDC) 的比较分析

我们研究了过表达草莓属 vesca L. cv. 的影响。Rügen S-腺苷-l-甲硫氨酸合酶 (FvSAMS) 和脱羧酶 (FvSAMDC) 基因在对照和盐胁迫下的本氏烟草 Domin 植物中。根据先前的研究，两种蛋白质的过量生产增强了植物的非生物胁迫耐受性，但尚未在一个实验系统中研究这两种酶。我们发现遭受长期盐胁迫的转基因植物比野生型 (WT) 表现出更高水平的耐受性。与早期的几项研究相比，在我们的实验系统中没有观察到乙烯和多胺生物合成之间的拮抗作用。与 FvSAMS 相比，FvSAMDC 的过表达在对照和盐胁迫条件下对植物生理参数的影响更大。根据在 FvSAMDC 品系中测量的数据，游离多胺水平与脯氨酸含量以及乙烯含量之间似乎呈正相关，而游离多胺水平与木质素含量之间呈负相关。暴露于盐胁迫的植物。转化载体包含 CaMV35S 启动子、与合成绿色荧光蛋白 (sGFP) 融合的 FvSAMS 和 FvSAMDC 的编码序列。我们检测了两种酶的亚细胞定位，并检查了它们分布中可能的压力引起的变化。在 FvSAMS::sGFP 核、核仁、细胞质（靠近质膜）、质体膜的情况下，而在 FvSAMDC::sGFP 核和同质细胞质定位中检测到。所以，