Dataset Information

Unbiased characterization of genotype-dependent metabolic regulations by metabolomic approach in Arabidopsis thaliana

ABSTRACT: Metabolites are not only the catalytic products of enzymatic reactions but also the active regulators or the ultimate phenotype of metabolic homeostasis in highly complex cellular processes. The modes of regulation at the metabolome level can be revealed by metabolic networks. We investigated the metabolic network between wild-type and 2 mutant (methionine-over accumulation 1 [mto1] and transparent testa4 [tt4]) plants regarding the alteration of metabolite accumulation in Arabidopsis thaliana. In the GC-TOF/MS analysis, we acquired quantitative information regarding over 170 metabolites, which has been analyzed by a novel score (ZMC, z-score of metabolite correlation) describing a characteristic metabolite in terms of correlation. Although the 2 mutants revealed no apparent morphological abnormalities, the overall correlation values in mto1 were much lower than those of the wild-type and tt4 plants, indicating the loss of overall network stability due to the uncontrolled accumulation of methionine. In the tt4 mutant, a new correlation between malate and sinapate was observed although the levels of malate, sinapate, and sinapoylmalate remain unchanged, suggesting an adaptive reconfiguration of the network. Gene-expression correlations presumably responsible for these metabolic networks were determined using the metabolite correlations as clues. Two Arabidopsis mutants, mto1 and tt4, exhibited the following changes in entire metabolome networks: the overall loss of metabolic stability (mto1) or the generation of a metabolic network of a backup pathway for the lost physiological functions (tt4). The expansion of metabolite correlation to gene-expression correlation provides detailed insights into the systemic understanding of the plant cellular process regarding metabolome and transcriptome.

INSTRUMENT(S): Leco Pegasus III

SUBMITTER: Atsushi Fukushima

PROVIDER: MTBLS40 | MetaboLights | 2014-03-01

REPOSITORIES: MetaboLights

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Dataset's files

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			Action	DRS
	MTBLS40	Other
	FILES	Other
	a_MTBLS40_gc0001_metabolite_profiling_mass_spectrometry.txt	Txt
	i_Investigation.txt	Txt
	m_MTBLS40_gc0001_metabolite_profiling_mass_spectrometry_v2_maf.tsv	Tabular

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Publications

Unbiased characterization of genotype-dependent metabolic regulations by metabolomic approach in Arabidopsis thaliana.

Kusano Miyako M Fukushima Atsushi A Arita Masanori M Jonsson Pär P Moritz Thomas T Kobayashi Makoto M Hayashi Naomi N Tohge Takayuki T Saito Kazuki K

BMC systems biology 20071121

<h4>Background</h4>Metabolites are not only the catalytic products of enzymatic reactions but also the active regulators or the ultimate phenotype of metabolic homeostasis in highly complex cellular processes. The modes of regulation at the metabolome level can be revealed by metabolic networks. We investigated the metabolic network between wild-type and 2 mutant (methionine-over accumulation 1 [mto1] and transparent testa4 [tt4]) plants regarding the alteration of metabolite accumulation in Ara ...[more]

PMID: 18028551

Publication: 1/2

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