Baek Seung-A, Im Kyung-Hoan, Park Sang Un, Oh Sung-Dug, Choi Jaehyuk, Kim Jae Kwang
Division of Life Sciences and Bio-Resource and Environmental Center, College of Life Sciences and Bioengineering, Incheon National University, Incheon 22012, Korea.
Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea.
Plants (Basel). 2019 Sep 23;8(10):361. doi: 10.3390/plants8100361.
Nitrogen (N) is a macronutrient important for the survival of plants. To investigate the effects of N deficiency, a time-course metabolic profiling of radish sprouts was performed. A total of 81 metabolites-including organic acids, inorganic acid, amino acids, sugars, sugar alcohols, amines, amide, sugar phosphates, policosanols, tocopherols, phytosterols, carotenoids, chlorophylls, and glucosinolates-were characterized. Principal component analysis and heat map showed distinction between samples grown under different N conditions, as well as with time. Using PathVisio, metabolic shift in biosynthetic pathways was visualized using the metabolite data obtained for 7 days. The amino acids associated with glucosinolates accumulated as an immediate response against -N condition. The synthesis of pigments and glucosinolates was decreased, but monosaccharides and γ-tocopherol were increased as antioxidants in radish sprouts grown in -N condition. These results indicate that in radish sprouts, response to N deficiency occurred quickly and dynamically. Thus, this metabolic phenotype reveals that radish responds quickly to N deficiency by increasing the content of soluble sugars and γ-tocopherol, which acts as a defense mechanism after the germination of radish seeds.
氮（N）是植物生存所必需的大量营养素。为了研究缺氮的影响，对萝卜芽进行了时间进程代谢谱分析。共鉴定出81种代谢物，包括有机酸、无机酸、氨基酸、糖类、糖醇、胺类、酰胺、糖磷酸盐、多廿醇、生育酚、植物甾醇、类胡萝卜素、叶绿素和硫代葡萄糖苷。主成分分析和热图显示了不同氮条件下生长的样品之间以及随时间的差异。使用PathVisio，利用7天获得的代谢物数据可视化生物合成途径中的代谢变化。与硫代葡萄糖苷相关的氨基酸作为对缺氮条件的即时反应而积累。在缺氮条件下生长的萝卜芽中，色素和硫代葡萄糖苷的合成减少，但单糖和γ-生育酚作为抗氧化剂增加。这些结果表明，在萝卜芽中，对缺氮的反应迅速而动态。因此，这种代谢表型表明，萝卜种子发芽后，通过增加可溶性糖和γ-生育酚的含量来快速响应缺氮，这是一种防御机制。
