Short-term inhibition of glutamine synthetase leads to reprogramming of amino acid and lipid metabolism in roots and leaves of tea plant (Camellia sinensis L.)
Short-term inhibition of glutamine synthetase leads to reprogramming of amino acid and lipid metabolism in roots and leaves of tea plant (Camellia sinensis L.)
复制标题
谷氨酰胺合成酶的短期抑制会导致茶树根和叶中氨基酸和脂质代谢的重新编程（Camellia sinensis L.）
DOI：
10.1186/s12870-019-2027-0
复制
发表时间：
2019-10-15
影响因子：
5.3
通讯作者：
Ruan, Jianyun
中科院分区：
文献类型：
--
作者：
Liu, Mei-Ya;Tang, Dandan;Ruan, Jianyun
背景
氮素营养显著影响茶树品质相关物质的代谢和积累。氮素代谢受到短期抑制对茶树根和叶的影响，其生理和分子机制目前还知之甚少。
结果
在这项研究中，我们进行了茶树谷氨酰胺合成酶（GS），蛋氨酸亚砜亚胺（MSX）的特异性抑制剂，短时间（30分钟），并研究了抑制氮代谢的转录组和代谢组的质量相关化合物的影响。结果表明，MSX处理显著抑制了茶树根和叶的GS活性，两种组织类型对GS抑制均表现出敏感的代谢反应。在茶叶中，茶氨酸的水解随着茶氨酸和游离铵含量的增加而减少。所有其他氨基酸的生物合成受到抑制，含氮脂类的含量下降，表明GS的短期抑制降低了茶叶中的N再利用水平。与糖酵解和三羧酸（TCA）循环相关的代谢产物在GS阻遏后积累，而氨基酸如甘氨酸、丝氨酸、异亮氨酸、苏氨酸、亮氨酸和缬氨酸的含量在MXS处理组中下降。我们推测氨基酸的生物合成受糖酵解和TCA循环的反馈回路的影响。
结论
总之，我们的数据表明，GS阻遏在茶树导致氨基酸和脂质代谢途径的重编程。
Background
Nitrogen (N) nutrition significantly affected metabolism and accumulation of quality-related compounds in tea plant (Camellia sinensis L.). Little is known about the physiological and molecular mechanisms underlying the effects of short-term repression of N metabolism on tea roots and leaves for a short time.
Results
In this study, we subjected tea plants to a specific inhibitor of glutamine synthetase (GS), methionine sulfoximine (MSX), for a short time (30 min) and investigated the effect of the inhibition of N metabolism on the transcriptome and metabolome of quality-related compounds. Our results showed that GS activities in tea roots and leaves were significantly inhibited upon MSX treatment, and both tissue types showed a sensitive metabolic response to GS inhibition. In tea leaves, the hydrolysis of theanine decreased with the increase in theanine and free ammonium content. The biosynthesis of all other amino acids was repressed, and the content of N-containing lipids declined, suggesting that short-term inhibition of GS reduces the level of N reutilization in tea leaves. Metabolites related to glycolysis and the tricarboxylic acid (TCA) cycle accumulated after GS repression, whereas the content of amino acids such as glycine, serine, isoleucine, threonine, leucine, and valine declined in the MXS treated group. We speculate that the biosynthesis of amino acids is affected by glycolysis and the TCA cycle in a feedback loop.
Conclusions
Overall, our data suggest that GS repression in tea plant leads to the reprogramming of amino acid and lipid metabolic pathways.