Cadena-Zamudio Jorge David, Monribot-Villanueva Juan Luis, Pérez-Torres Claudia-Anahí, Alatorre-Cobos Fulgencio, Guerrero-Analco José Antonio, Ibarra-Laclette Enrique
Red de Estudios Moleculares Avanzados (REMAV), Instituto de Ecología, A.C. (INECOL), Xalapa 91073, Veracruz, Mexico.
Consejo Nacional de Ciencia y Tecnología, Unidad de Bioquímica y Biología Molecular de Plantas, Merida 97205, Yucatan, Mexico.
Metabolites. 2023 Sep 18;13(9):1021. doi: 10.3390/metabo13091021.
As sessile organisms, plants develop the ability to respond and survive in changing environments. Such adaptive responses maximize phenotypic and metabolic fitness, allowing plants to adjust their growth and development. In this study, we analyzed the metabolic plasticity of in response to nitrate deprivation by untargeted metabolomic analysis and using wild-type (WT) genotypes and the loss-of-function / double mutant. Secondary metabolites were identified using seedlings grown on a hydroponic system supplemented with optimal or limiting concentrations of N (4 or 0.2 mM, respectively) and harvested at 15 and 30 days of age. Then, spectral libraries generated from shoots and roots in both ionization modes (ESI +/-) were compared. Totals of 3407 and 4521 spectral signals (m/z_rt) were obtained in the ESI and ESI modes, respectively. Of these, approximately 50 and 65% were identified as differentially synthetized/accumulated. This led to the presumptive identification of 735 KEGG codes (metabolites) belonging to 79 metabolic pathways. The metabolic responses in the shoots and roots of WT genotypes at 4 mM of N favor the synthesis/accumulation of metabolites strongly related to growth. In contrast, for the / double mutant (similar as the WT genotype at 0.2 mM N), metabolites identified as differentially synthetized/accumulated help cope with stress, regulating oxidative stress and preventing programmed cell death, meaning that metabolic responses under N starvation compromise growth to prioritize a defensive response.
作为固着生物，植物发展出在不断变化的环境中做出反应并生存的能力。这种适应性反应使表型和代谢适应性最大化，使植物能够调整其生长和发育。在本研究中，我们通过非靶向代谢组学分析，并使用野生型（WT）基因型和功能缺失/双突变体，分析了植物对硝酸盐剥夺的代谢可塑性。使用在补充有最佳或限制浓度氮（分别为4或0.2 mM）的水培系统上生长的幼苗鉴定次生代谢产物，并在15天和30天时收获。然后，比较了在两种电离模式（ESI+/-）下从地上部和根部生成的光谱库。在ESI和ESI模式下分别获得了3407和4521个光谱信号（m/z_rt）。其中，约50%和65%被鉴定为差异合成/积累。这导致推测鉴定出属于79条代谢途径的735个KEGG编码（代谢物）。在4 mM氮条件下，WT基因型地上部和根部的代谢反应有利于与生长密切相关的代谢物的合成/积累。相反，对于/双突变体（与0.2 mM氮条件下的WT基因型相似），鉴定为差异合成/积累的代谢物有助于应对胁迫，调节氧化应激并防止程序性细胞死亡，这意味着氮饥饿条件下的代谢反应会牺牲生长以优先进行防御反应。
