Abstract
Various metabolites accumulate in response to environmental stress such as drought in higher plants. A lot of drought-inducible genes have been identified by using microarray analysis in Arabidopsis (Seki et al., 2002). To study genes involved in metabolic networks of plant in drought-stress response, we analyzed transcriptome and metabolome profilings of Arabidopsis plants under drought stress. Metabolite profiling using LC/MS, GC/MS and CE/MS showed an accumulation of aromatic amino acids, branch-chain amino acids, polyamines and flavonoids in response to drought stress. We found that genes involved in biosynthesis of these metabolites were also induced under drought stress, which suggests that drought stress might regulate key genes that function in these metabolic pathways. ABA is known to play an important role for stomata closure or gene expression in drought stress response. We are now analyzing the metabolites that are regulated by ABA through the analysis of ABA deficient mutants.
