Subcellular reprogramming of metabolism during cold acclimation in Arabidopsis thaliana
Subcellular reprogramming of metabolism during cold acclimation in Arabidopsis thaliana
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DOI：
10.1111/pce.12836
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发表时间：
2017-05-01
影响因子：
7.3
通讯作者：
Heyer, Arnd G.
中科院分区：
文献类型：
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作者：
Hoermiller, Imke I.;Naegele, Thomas;Heyer, Arnd G.
植物叶片中的代谢物在低温下的变化包括大量代谢物在亚细胞室之间的重新分配。因此，整个细胞水平的代谢物测定可能不足以解释细胞化合物的功能意义。为了在单个亚细胞室水平上研究冷诱导的代谢物动力学，开发了一个综合平台，该平台将气相色谱-质谱联用(GC-MS)定量代谢物分析与非水分离技术相结合，允许胞浆、液泡和质室的分离。为了研究冷驯化与代谢亚细胞重编程之间的相互作用，将两个代表蔗糖和淀粉之间碳水化合物代谢转移对极的拟南芥突变体与Col-0野生型在冷驯化前后进行了比较。对数据集的多变量分析显示，分隔对代谢物浓度的显性影响受环境条件和遗传决定因素的调节。而对于胞质磷酸葡萄糖变位酶(PGM)的无淀粉突变体和蔗糖磷酸合成酶A1缺陷突变体，根据亚细胞分解的代谢物图谱可以发现代谢限制，特别是在低温下，只有PGM具有较低的耐冻性。PGM的代谢特征表明，氧化还原失衡可能是冷适应能力降低的原因。
Metabolite changes in plant leaves during exposure to low temperatures involve re-allocation of a large number of metabolites between sub-cellular compartments. Therefore, metabolite determination at the whole cell level may be insufficient for interpretation of the functional significance of cellular compounds. To investigate the cold-induced metabolite dynamics at the level of individual sub-cellular compartments, an integrative platform was developed that combines quantitative metabolite profiling by gas chromatography coupled to mass spectrometry (GC-MS) with the non-aqueous fractionation technique allowing separation of cytosol, vacuole and the plastidial compartment. Two mutants of Arabidopsis thaliana representing antipodes in the diversion of carbohydrate metabolism between sucrose and starch were compared to Col-0 wildtype before and after cold acclimation to investigate interactions of cold acclimation with subcellular re-programming of metabolism. A multivariate analysis of the data set revealed dominant effects of compartmentation on metabolite concentrations that were modulated by environmental condition and genetic determinants. While for both, the starchless mutant of plastidial phospho-gluco mutase (pgm) and a mutant defective in sucrose-phosphate synthase A1, metabolic constraints, especially at low temperature, could be uncovered based on subcellularly resolved metabolite profiles, only pgm had lowered freezing tolerance. Metabolic profiles of pgm point to redox imbalance as a possible reason for reduced cold acclimation capacity.