Project/Area Number |
18370017
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
植物生理・分子
|
Research Institution | Tokyo University of Agriculture and Technology |
Principal Investigator |
YOSHIHIRO Ozeki Tokyo University of Agriculture and Technology, The Institute of Symbiotic Science and Technology, Professor (50185592)
|
Co-Investigator(Kenkyū-buntansha) |
KODAMA Hiroaki Chiba University, Graduate School of Horticulture, Associate Professor (70302536)
|
Project Period (FY) |
2006 – 2007
|
Project Status |
Completed (Fiscal Year 2007)
|
Budget Amount *help |
¥16,010,000 (Direct Cost: ¥15,200,000、Indirect Cost: ¥810,000)
Fiscal Year 2007: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
Fiscal Year 2006: ¥12,500,000 (Direct Cost: ¥12,500,000)
|
Keywords | betalain / biosynthesis / cyclo-DOPA / four o'clocks / globe amaranth / glucosyltransferase / phenylpropanoid / 遺伝子 / 酵素 / 植物 / 生理学 / マイクロアレイ |
Research Abstract |
cDNAs encoding for the homologous gene of DOPA 4,5 dioxygenase (DOD), which was a key enzyme involved in betalain biosynthesis, were isolated from four o'clocks, Arabidopsis, torenia and carnation. The cDNA was introduced into a expression vector and transformed into Escherichia coli In the crude extract prepared from the E. coli, DOD activity was detected to form betalamic acid, indicating that the enzymatic properties of DOD could be elucidated using this extract in vitro. Because betalains were modified by sugar moieties at the intermediate step of cyclo-DOPA of the synthetic pathway, cDNAs for cyclo-DOPA glucosyltransferase (cDOPA5GT) were isolated from four o'clocks, portulaca and globe amaranth. The amino acid sequences of cDOPA5GT cDNAs derived from these plant species consisted of a separated clade from others, suggesting that cDOPA5GT might have arisen early during the evolutionary divergence and established of the Caryophyllales except for Dianthus. The specific activities of other GTs encoded in cDNAs derived from these species isolated simultaneously were analyzed by heterologous expression in E. coli. The GT encoded in a cDNA derived from globe amaranth showed broad specific activity to phenylpropanoids including p-coumaric acid, caffeic acid, sinapic acid and ferulic acid as sugar acceptors. Using this cDNA together with the cDNA of Arabidopsis sucrose synthase, the efficient synthetic method for phenylpropanoid-glucosides was established. These phenylpropanoid-glucosides purified by high performance liquid chromatography could be used as good acyl-donors for anthocyanin acyltransfarase assays.
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