Guan Cong, Cui Xin, Liu Hua-Yue, Li Xue, Li Meng-Qi, Zhang Yun-Wei
College of Grassland Science and Technology, China Agricultural University, Beijing, China.
Beijing Key Laboratory for Grassland Science, China Agricultural University, Beijing, China.
Front Plant Sci. 2020 Feb 14;11:46. doi: 10.3389/fpls.2020.00046. eCollection 2020.
Understanding the regulation of proline metabolism necessitates the suppression of two synthetase enzyme () genes performed in switchgrass ( L.). The results reveal that overexpressing and increased salt tolerance. Additionally, transcript levels of spermidine (Spd) and spermine (Spm) synthesis and metabolism related genes were upregulated in -transgenic plants and downregulated in the transformants. According to salt stress assay and the measurement of transcript levels of Polyamines (PAs) metabolism-related genes, enzyme may not only be the key regulator of proline biosynthesis in switchgrass, but it may also indirectly affect the entire subset of pathway for ornithine to proline or to putrescine (Put). Furthermore, application of proline prompted expression levels of Spd and Spm synthesis and metabolism-related genes in both - and WT plants, but transcript levels were even lower in - compared to WT plants under salt stress condition. These results suggested that exogenous proline could accelerate polyamines metabolisms under salt stress. Nevertheless, the enzymes involved in this process and the potential functions remain poorly understood. Thus, the aim of this study is to reveal how proline functions with PAs metabolism under salt stress in switchgrass.
了解脯氨酸代谢的调控需要抑制柳枝稷（Panicum virgatum L.）中两个合成酶基因（）的表达。结果表明，过表达和可提高耐盐性。此外，在转基因植物中转录水平上调，而在转基因植物中转录水平下调。根据盐胁迫试验以及多胺（PAs）代谢相关基因转录水平的测定，酶不仅可能是柳枝稷中脯氨酸生物合成的关键调节因子，还可能间接影响从鸟氨酸到脯氨酸或腐胺（Put）的整个途径子集。此外，脯氨酸的施用促使转基因植物和野生型（WT）植物中与Spd和Spm合成及代谢相关基因的表达水平升高，但在盐胁迫条件下，转基因植物中的转录水平甚至低于野生型植物。这些结果表明，外源脯氨酸可以在盐胁迫下加速多胺代谢。然而，参与这一过程的酶及其潜在功能仍知之甚少。因此，本研究的目的是揭示在盐胁迫下柳枝稷中脯氨酸如何与多胺代谢协同发挥作用。
