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• Laboratory of Biopharmaceutics
• Laboratory of Applied Phrmacology
• Laboratory of Biorecognition Chemistry
• Laboratory of Cancer Cell Biology
• Laboratory of Chemical Biology
• Laboratory of Synthetic and
  Medicinal Chemistry
• Laboratory of Molecular Neurobiology
• Laboratory of Gene Regulation
• Laboratory of Molecular Cell Biology
• Laboratory of Medicinal Bioresources
• Laboratory of Synthetic and Biomolecular Organic Chemistry
• Laboratory of Biointerface Chemistry
• Laboratory of Structual Biology
• Laboratory of Phrmaceutical Physiology
• Laboratory of Medical Pharmaceutics
  Laboratory of Community Pharmacy
• Laboratory of Plant Resource Sciences
• Laboratory of Clinical Pharmacology
• Laboratory of Clinical Pharmacokinetics
• Laboratory of Pharmaceutical Therapy
  and Neuropharmacology
• Department of Hospital Pharmacy
• Department of Pharmaceutical Technology
• Division of Pharmacognosy
• Division of Natural Products Chemistry
• Division of Kampo-Pharmaceutics
• Division of Medicinal Pharmacology
• Division of Pathogenic Biochemistry
• Division of Gastrointestinal Pathophysiology
• Division of Neuromedical Science
• Division of Nutritional Biochemistry
• Division of Kampo Diagnostics
• Division of Natural Drug Discovery
• Molecular Genetics Research Laboratory, Life Science Research Center

Our research interests are ; 1) the structures, reaction mechanisms and physiological regulation of the enzyme proteins catalyzing natural products biosynthesis in higher plants, and 2) the signal transduction mechanisms involved in the enhancement of secondary metabolites production in response to various external stimuli in plant cells. We attempt to understand the physiological, biochemical and molecular regulation of plant secondary metabolism for the development of novel methodology to improve the production of useful natural products of pharmaceutical significance (in vitro cell culture, catalytically-modified enzyme proteins, and transgenic plants).

At present, special attention is focused on the elucidation of signaling pathway of jasmonic acid, a plant hormone derived from fatty acid which evokes the biosynthesis of various defense-related natural products. We study how plants perceive and respond to this external signal by modifying their cell physiological programs to produce diterpene and sesquiterpene compounds. We have identified a new molecular network for Ca^2＋ signal transduction in plants which leads to the enhanced production of the plant secondary metabolites. Recently, we have also found that, at downstream these early signaling events, plants respond to the stimulation with jasmonic acid by post-translational modification of plant-specific monomer GTP-binding proteins, Rac/Rop GTPases, followed by the plasma membrane-oriented translocation of these mediators. An attempt is made to ‘manipulate’ these signaling processes in higher plant cells for the control of natural products biosynthesis employing various transgenic plants.

Left, Seedlings of Atropa belladonna germinated under sterilized conditions as the host for transformation experiments ; Center, Generation of transformed hairy root tissues from leaf segments of A. belladonna by co-expression of root-forming rol-cluster with plant Ca^2＋-cascade related genes ; Right, Regenerated young seedlings of A. belladonna transformed with Rac/Rop GTPase genes encoding unique monomeric GTP-binding proteins of higher plants.