Metabolic Systems Research Team

Metabolism is finely regulated in a complicated way, as it comprises the basis of life. Especially, plant’s and bacterial metabolism is an important base not only for their own lives but also for animal lives and human society by providing nutrient and functional compounds. Aiming at grasping a whole picture of metabolism, we develop metabolomics techniques, predict metabolic reaction network by mathematical modeling using omics data, and explore metabolic gene functions by molecular biology, biochemistry and molecular genetics. We also aim at improvement of plant’s and bacterial productivity of useful metabolites by use of our findings.

Research Fields

Biology & Biochemistry / Molecular Biology & Genetics / Agricultural Sciences / Plant & Animal Science

• Analysis of metabolic reaction network by mathematical modeling
• Large-scale analysis of metabolic profiles by a high-throughput methodology (Widely targeted metabolomics)
• Functional identification of genes involved in metabolism
• Metabolic engineering of cyanobacteria
• Elucidation of metabolic function in plant ontogenesis and host plant-parasite plant interaction

Publications

1. Okazaki, Y. Otsuki, H., Narisawa, T., Kobayashi, M., Sawai, S., Kamide, Y., Kusano, M., Aoki, T., Hirai, M.Y., and Saito, K. (2013)
   "Lipidomics revealed a novel plant lipid class playing a critical role in mitigation for phosphate depletion."
   Nature Communications in press
2. Sriyudthsak, K., Shiraishi, F., and Hirai, M.Y. (2013)
   "Identification of a metabolic reaction network from time-series data of metabolite concentrations."
   PLoS One 8, e51212.
3. Nakabayashi, R., Sawada, Y., Yamada, Y., Suzuki, M., Hirai, M.Y., Sakurai, T., and Saito, K. (2013)
   "Combination of liquid chromatography-fourier transform ion cyclotron resonance-mass spectrometry with (13)C-labeling for chemical assignment of sulfur-containing metabolites in onion bulbs."
   Anal Chem. 2013 Jan 17. [Epub ahead of print]
4. Sawada, Y., Nakabayashi, R., Yamada, Y., Suzuki, M., Sato, M., Sakata, A., Akiyama, K., Sakurai, T., Matsuda, F., Aoki, T., Hirai, M.Y., and Saito, K. (2012)
   "RIKEN tandem mass spectral database (ReSpect) for phytochemicals: a plant-specific MS/MS-based data resource and database."
   Phytochemistry 82, 38-45.
5. Matsuda, F., Nakabayashi, R., Sawada, Y., Suzuki, M., Hirai, M.Y., Kanaya S., and Saito K. (2011)
   "Mass spectra-based framework for automated structural elucidation of metabolome data to explore phytochemical diversity."
   Frontiers Plant Sci. 2, 40.
6. Osanai, T., Oikawa, A., Azuma, M., Tanaka, K., Saito, K., Hirai, M.Y., and Ikeuchi, M. (2011)
   "Genetic engineering of group 2 sigma factor SigE widely activates expressions of sugar catabolic genes in Synechocystis species PCC 6803."
   J. Biol. Chem. 286, 30962-30971.
7. Hanada, K., Sawada, Y., Kuromori, T., Klausnitzer, R., Saito, K., Toyoda, T., Shinozaki, K., Li, W.H. and Hirai, M.Y. (2011)
   "Functional compensation of primary and secondary metabolites by duplicate genes in Arabidopsis thaliana."
   Mol. Biol. Evol. 28, 377-382.
8. Matsuda, F., Hirai, M.Y., Sasaki, E., Akiyama, K., Yonekura-Sakakibara, K., Provart, N.J., Sakurai, T., Shimada, Y. and Saito, K. (2009a)
   "AtMetExpress development: A phytochemical atlas of Arabidopsis thaliana development."
   Plant Physiol. 152, 566-578.
9. Sawada, Y., Akiyama, K., Sakata, A., Kuwahara, A., Otsuki, H., Sakurai, T., Saito, K., and Hirai, M.Y. (2009a)
   "Widely targeted metabolomics based on large-scale MS/MS data for elucidating metabolite accumulation patterns in plants."
   Plant Cell Physiol. 50, 37-47.
10. Hirai, M.Y., Sugiyama, K., Sawada, Y., Tohge, T., Obayashi, T., Suzuki, A., Araki, R., Sakurai, N., Suzuki, H., Aoki, K., Goda, H., Nishizawa, O.I., Shibata, D., and Saito, K. (2007)
    "Omics-based identification of Arabidopsis Myb transcription factors regulating aliphatic glucosinolate biosynthesis."
    Proc. Natl. Acad. Sci. U. S. A. 104, 6478-6483.