Many horticultural and natural plant species have variegated leaves, that is, patchy leaves with green and non-green or white areas. Specific studies on the metabolism of variegated leaves are scarce and although white (non-green) areas have been assumed to play the role of a ‘nitrogen store', there is no specific studies showing the analysis of nitrogenous metabolites and the dynamics of nitrogen assimilation. Here, we examined the metabolism of variegated leaves of Pelargonium × hortorum. We show that white areas have a larger N : C ratio, more amino acids, with a clear accumulation of arginine. Metabolomic analyses revealed clear differences in the chemical composition, suggesting contrasted metabolic commitments such as an enhancement of alkaloid biosynthesis in white areas. Using isotopic labelling followed by nuclear magnetic resonance or liquid chromatography/mass spectrometry, we further showed that in addition to glutamine, tyrosine and tryptophan, N metabolism forms ornithine in green area and huge amounts of arginine in white areas. Fine isotopic measurements with isotope ratio mass spectrometry indicated that white and green areas exchange nitrogenous molecules but nitrogen export from green areas is quantitatively much more important. The biological significance of the metabolic exchange between leaf areas is briefly discussed.

中文翻译：

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更正为：杂色叶中氮代谢功能分区的代谢组学表征。

许多园艺和天然植物种类都有杂色的叶子，即具有绿色和非绿色或白色区域的斑叶。杂色叶片代谢的具体研究很少，尽管白色（非绿色）区域被认为起着“氮存储”的作用，但尚无具体研究显示对氮代谢物和氮同化动力学的分析。 。在这里，我们检查了天竺葵×荷叶杂色叶的代谢。我们显示白色区域具有更大的N：C比，更多的氨基酸和精氨酸的明显积累。代谢组学分析揭示了化学成分上的明显差异，表明了相反的代谢作用，例如在白色区域生物碱生物合成的增强。使用同位素标记，然后进行核磁共振或液相色谱/质谱分析，我们进一步表明，除了谷氨酰胺，酪氨酸和色氨酸外，N代谢在绿色区域形成鸟氨酸，在白色区域形成大量精氨酸。用同位素比质谱法进行的精细同位素测量表明，白色和绿色区域交换含氮分子，但从绿色区域输出的氮在数量上更为重要。