Metabolomics Reveals Distinct Carbon and Nitrogen Metabolic Responses to Magnesium Deficiency in Leaves and Roots of Soybean [Glycine max (Linn.) Merr.]

Abstract

Magnesium (Mg) deficiency, a widespread yet overlooked problem in agriculture, has been reported to retard plant growth and development, through affecting key metabolic pathways. However, the metabolic responses of plant to Mg deficiency is still not fully understood. Here we report a metabolomic study to evaluate the metabolic responses to Mg deficiency in soybean leaves and roots. Hydroponic grown soybean were exposed to Mg starvation for 4 and 8 days, respectively. Metabolic changes in the first mature trifoliolate leaves and roots were quantified by conducting GC-TOF-MS based metabolomic analysis. Principal component analysis (PCA) showed that Mg deficient plants became distinguishable from controls at 4 days after stress (DAS) at metabolic level, and were clearly discriminated at 8 DAS. Mg deficiency could cause large metabolite alterations on carbon and nitrogen metabolism. At 8 DAS, carbon allocation from shoot to root is decreased by Mg deficiency. Remarkably, most amino acids (such as phenylalanine, asparagine, leucine, isoleucine, glycine, glutamine, and serine) showed pronounced accumulation in the leaves, while most organic acids (including pyruvic acid, citric acid, 2-keto-glutaric acid, succinic acid, fumaric acid, and malic acid) were significantly decreased in the roots. Our study shows that the carbon and nitrogen metabolic responses are distinct in leaves and roots under Mg deficiency.

Pooled CRISPR/Cas9 reveals redundant roles of plastidial phosphoglycerate kinases in carbon fixation and metabolism

“…Five milligrams of each lyophilized sample was extracted with 1 ml prechilled and degassed extraction buffer comprised of chloroform, methanol and water (1:2.5:1 [v/v/v]), and 12 μl arabitol (1 mg/ml) was added as internal standard. Derivatization, GC‐TOF‐MS, metabolite identification and data normalization were performed as described previously (Yang et al ., ). For multivariate and univariate analysis, MetaboAnalyst online tools were used as described previously (Xia et al ., ; Yang et al ., ).…”

“…Derivatization, GC‐TOF‐MS, metabolite identification and data normalization were performed as described previously (Yang et al ., ). For multivariate and univariate analysis, MetaboAnalyst online tools were used as described previously (Xia et al ., ; Yang et al ., ). For univariate analysis, both Student's t ‐test and fold‐change analysis were performed using MetaboAnalyst.…”

“…For chlorophyll content measurement, 0.2 g fresh leaves were extracted with 80% acetone, then centrifuged at 1800 g for 4 min. The supernatant was measured for optical density by spectrometer (V‐1600, MAPADA Instruments Co., Ltd., Shanghai, China) and chlorophyll content was calculated as described previously (Yang et al ., ).…”

Functioning of potassium and magnesium in photosynthesis, photosynthate translocation and photoprotection

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Metabolomics biotechnology, applications, and future trends: a systematic review

“…It was found that there were signicant differences in carbon and nitrogen metabolic responses between leaves and roots under magnesium deciency. 90 Nitrogen plays an important role in plant growth. Nitrogen is the major component of protein.…”