SE144:/MS1
From Metabolonote
Sample Set Information
| ID | SE144 |
|---|---|
| Title | Metabolomics data reveal a crucial role of cytosolic glutamine synthetase 1;1 in coordinating metabolic balance in rice. |
| Description | Rice plants grown in paddy fields preferentially use ammonium as a source of inorganic nitrogen. Glutamine synthetase (GS) catalyses the conversion of ammonium to glutamine. Of the three genes encoding cytosolic GS in rice, OsGS1;1 is critical for normal growth and grain filling. However, the basis of its physiological function that may alter the rate of nitrogen assimilation and carbon metabolism within the context of metabolic networks remains unclear. To address this issue, we carried out quantitative comparative analyses between the metabolite profiles of a rice mutant lacking OsGS1;1 and its background wild type (WT). The mutant plants exhibited severe retardation of shoot growth in the presence of ammonium compared with the WT. Overaccumulation of free ammonium in the leaf sheath and roots of the mutant indicated the importance of OsGS1;1 for ammonium assimilation in both organs. The metabolite profiles of the mutant line revealed: (i) an imbalance in levels of sugars, amino acids and metabolites in the tricarboxylic acid cycle, and (ii) overaccumulation of secondary metabolites, particularly in the roots under a continuous supply of ammonium. Metabolite-to-metabolite correlation analysis revealed the presence of mutant-specific networks between tryptamine and other primary metabolites in the roots. These results demonstrated a crucial function of OsGS1;1 in coordinating the global metabolic network in rice plants grown using ammonium as the nitrogen source. |
| Authors | Kusano M, Tabuchi M, Fukushima A, Funayama K, Diaz C, Kobayashi M, Hayashi N, Tsuchiya YN, Takahashi H, Kamata A, Yamaya T, Saito K. |
| Reference | Plant J. 2011 May;66(3):456-66. |
| Comment |
Analytical Method Details Information
| ID | MS1 |
|---|---|
| Title | Metabotyping and metabolite profiling analysis |
| Instrument | GC:Agilent 6890N MS:LECO Pegasus III |
| Instrument Type | |
| Ionization | EI |
| Ion Mode | positive |
| Description | We used the three different tissues (LB, LS and roots) to perform metabolite phenotyping and profiling using GC-TOF-MS (Kusano et al., 2007a). Metabotyping was conducted using six independent seedlings for WT, two independent knockout lines (NC2373 and ND8037) and the corresponding null lines, respectively. Extracts from 5 mg (fresh weight, FW) samples were used for metabotyping. Extracts of 55.6 μg FW samples was injected into the GC-TOF-MS.We performed data pre-treatment and normalisation as described by Kusano et al. (2007a) and Redestig et al. (2009). For metabolite profiling, a total of 16–20 biological replicates were collected,extracted, derivatised and analysed. Extracts from 5 mg FW samples were used. Subsequently, extracts of 83.3 μg FW samples for the ammonium experiment and extracts of 55.6 μg FW samples for the water experiment were injected . |
| Comment_of_details |
