Résumé
Global changes in gene transcription (the transcriptome), and protein amount/activity (the proteome) ultimately effect metabolism and the metabolite content (the metabolome) of cells, tissues, and organs of plants. In the past, studies of plant metabolism focussed on one or a few genes, proteins, and/or metabolites. New tools have been developed to measure levels of thousands of gene transcripts and proteins in parallel (see Chapters 4.2-4.4), facilitating nonbiased, systems-wide investigations. To complement these ‘OMICS’ technologies, we use gas chromatography coupled to mass-spectroscopy together with bioinformatics tools to monitor changes in the levels of hundreds of metabolites in different organs. The methods described in this chapter provide qualitative and quantitative information about the Lotus metabolome, which together with transcriptome and proteome analyses, enable new insights into the links between genotype and phenotype at the whole-system level.