Metabolomics Research Group

Metabolomics involves in the identification and quantification of all metabolites in a cell, and correlating these to genomic functions. Metabolome in the plant kingdom is extremely diverse chemically, with estimates indicating as many as 200,000 different types of chemical substances. The various compounds produced by plants are important for the existence of the plant itself, and also play a vital role in our lives as food, industrial materials, energy and medicines. Our group performs high-throughput metabolomics analyses by high-performance mass spectrometry. These non-targeted metabolomic analyses are applied to the identification of unknown gene functions and elucidation of metabolic networks. We are investigating the basic principles behind the wide variety of plant production functions, using Arabidopsis as a model. We are also elucidating the production systems for specialized plant products in crops, medicinal plants and other useful plants at a genome level, regarded as Phytochemical Genomics. Another important aspect of our research is the application of the basic findings from these results to development of sustainable resources.

Research Fields

Chemistry / Biology & Biochemistry / Molecular Biology & Genetics / Pharmacology & Toxicology / Agricultural Sciences / Plant & Animal Science / Multidisciplinary

• Development of precision, high-throughput analytical techniques using mass spectrometry for plant metabolomics
• Database construction for metabolite identification and bioinformatics for metabolomic data analysis
• Metabolomic analysis accompanying cell and functional differentiation, stress responses, and linking to genes’ function in Arabidopsis, rice, tomato, soybeans and other crops
• Integrated –omics study for identification of new genes and networks involved in the biosynthesis and accumulation of flavonoids, terpenoids, alkaloids, sulfur-containing metabolites, lipids, sugars and other substances in non-model plants, and their application to the production of useful substance

Publications

1. Okazaki, Y., Otsuki, H., Narisawa, T., Kobayashi, M., Sawai, S., Kamide, Y., Kusano, M., Aoki, T., Hirai, M. Y. and Saito, K.
   "A new class of plant lipid is essential for protection against phosphorus depletion"
   Nature Commun., in press (2013)
2. Bunsupa, S., Katayama, K., Ikeura, E., Oikawa, A., Toyooka, K., Saito, K. and Yamazaki, M.
   "Lysine decarboxylase catalyzes the first step of quinolizidine alkaloid biosynthesis and coevolved with alkaloid production in Leguminosae"
   Plant Cell, 24, 1202-1216 (2012)
3. Matsuda, F., Okazaki, Y., Oikawa, A., Kusano, M., Nakabayashi, R., Kikuchi, J., Yonemaru, J., Ebana, K., Yano, M. and Saito, K.
   "Dissection of genotype-phenotype associations in rice grains using metabolome quantitative trait loci analysis"
   Plant J., 70, 624–636 (2012)
4. Seki, H.*, Sawai, S. *, Ohyama, K. *, Mizutani, M., Ohnishi, T., Sudo, H., Odette Fukushima, E., Akashi, T., Aoki, T., Saito, K., and Muranaka, T.(*equal contribution)
   "Triterpene functional genomics in licorice for identification of CYP72A154 involved in the biosynthesis of glycyrrhizin"
   Plant Cell, 23, 4112-4123 (2011)
5. Kusano, M., Redestig, H., Hirai, T., Oikawa, A., Matsuda, F., Fukushima, A., Masanori, A., Watanabe, S., Yano, M., Hiwasa-Tanase, K., Ezura, H., and Saito, K.
   "Covering chemical diversity of genetically-modified tomatoes using metabolomics for objective substantial equivalence assessment"
   PLoS ONE, 6(2): e16989 (2011)
6. Chisato Masumoto, Shin-Ichi Miyazawa, Hiroshi Ohkawa, Takuya Fukuda, Yojiro Taniguchi, Seiji Murayama, Miyako Kusano, Kazuki Saito, Hiroshi Fukayama and Mitsue Miyao
   Phosphoenolpyruvate carboxylase intrinsically located in the chloroplast of rice plays a crucial role in ammonium assimilation.
   Proc. Natl. Acad. Sci. USA, 107, 5226-5231 (2010)
7. Atsushi Fukushima, Miyako Kusano, Norihito Nakamichi, Makoto Kobayashi, Naomi Hayashi, Hitoshi Sakakibara, Takeshi Mizuno, and Kazuki Saito
   Impact of clock-associated Arabidopsis pseudo-response regulators in metabolic coordination
   Proc. Natl. Acad. Sci. USA, 106, 7251-7256 (2009)
8. Yozo Okazaki, Mie Shimojima, Yuji Sawada, Kiminori Toyooka, Tomoko Narisawa, Keiichi Mochida, Hironori Tanaka, Fumio Matsuda, Akiko Hirai, Masami Yokota Hirai, Hiroyuki Ohta, and Kazuki Saito
   A chloroplastic UDP-Glucose pyrophosphorylase from Arabidopsis is the committed enzyme for the first step of sulfolipid biosynthesis
   Plant Cell, 21, 892–909 (2009)
9. Keiko Yonekura-Sakakibara, Takayuki Tohge, Fumio Matsuda, Ryo Nakabayashi, Hiromitsu Takayama, Rie Niida, Akiko Watanabe-Takahashi, Eri Inoue and Kazuki Saito
   Comprehensive flavonol profiling and transcriptome coexpression analysis leading to decoding gene-metabolite correlations in Arabidopsis
   Plant Cell, 20, 2160–2176 (2008)
10. Mutsumi Watanabe, Keiichi Mochida, Tomohiko Kato, Satoshi Tabata, Naoko Yoshimoto, Masaaki Noji and Kazuki Saito
    Comparative genomics and reverse genetics analysis reveal indispensable functions of the serine acetyltransferase gene family in Arabidopsis
    Plant Cell, 20, 2484-2496 (2008)

Organization