2002 Fiscal Year Final Research Report Summary
Chemical structure and function of phototropism-regulating substances in plants
Project/Area Number |
13480182
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Bioorganic chemistry
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Research Institution | University of Tsukuba |
Principal Investigator |
HASEGAWA Koji Institute of Applied Biochemistry, Professor, 応用生物化学系, 教授 (70094167)
|
Co-Investigator(Kenkyū-buntansha) |
KOSEMURA Seiji Keio University, Low Department, Associate Professor, 法学部, 助教授 (70231313)
YAMADA Kosumi Institute of Applied Biochemistry, Assistant, 応用生物化学系, 助手 (70292521)
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Project Period (FY) |
2001 – 2002
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Keywords | phototropism / light-induced growth inhibitor / Bruinsma-Hasegawa theory / Cholodny-Went theory / DIMBOA / MBOA / indole-3-acetonitrile / Arabidopsis thaliana |
Research Abstract |
Phototropism is a typical example of an environmental response in plants. From many accumulated findings it is suggested that phototropism is caused by the unequal lateral distribution of light-induced growth inhibitor(s) in the illuminated and the shaded sides affecting the auxin activity at unchanged, even auxin level (Bruinsma-Hasegawa theory, 1990). In the present study, we investigated chemical structure and formation of phototropism-regulatming substances in plants. Blue light-induced growth inhibitors were isolated from light-grown maize coleoptiles, and identified as DIMBOA and MBOA from their ^1H NMR spectra. From chemical analyzes, it can be concluded that phototropic stimulation induces conversion of the inactive DIMBOA glucoside into the active DIMBOA, which plays the essential role in the phototropism of maize coleoptiles, and then metabolizes into MBOA, which has a lower activity. From light-grown Arabidopsis thaliana hypocotyls, indole-3-acetonitrile (IAN) was isolated and identified as a blue light-induced growth inhibitor. IAN increased in the wild type upon phototropic stimulation, whereas it showed no change in the mutant that shows no phototropic response. From these results it is suggested that IAN plays an important role in the phototropism of Arabidopsis hypocotyls.
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Research Products
(12 results)