| Project/Area Number |
08660203
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
林産学
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| Research Institution | Nagoya University |
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Principal Investigator |
YASUDA Seiichi Nagoya University, School of Agricultural Sciences, Professor, 農学部, 教授 (80002070)
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| Co-Investigator(Kenkyū-buntansha) |
IMAI Takanori Nagoya University, School of Agricultural Sciences, Assis.Prof., 農学部, 助手 (20252281)
FUKUDA Tadanori Nagoya University, School of Agricultural Sciences, Professor, 農学部, 教授 (10023441)
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| Project Period (FY) |
1996 – 1997
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| Project Status |
Completed (Fiscal Year 1997)
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| Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1997: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1996: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | cell wall / cellulose / lignin / hemicellulose / tree / radio tracer / microautoradiography |
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| Research Abstract |
Selective radio-labeling of mannan in ginkgo and pine was achieved by the administration of D-mannose- [2-3H] in the presence of both glucan biosynthesis inhibitor and phenylalanine ammonia-lyase inhibitor, namely, 2-deoxy-D-glucose and L-a-aminooxy-b-phenylpropionic acid, respectively, to growing stems. To study the deposition and distribution of mannan during cell wall formation, the distribution of the radioactivity in differentiating xylem was visualized by microautoradiography. Radioactivity was incorporated into the cell walls for a long period from early stage to S3 (inner layr of secondary wall) formation stage. The incorporation was most significant at the stage following the start of S1 (outer layr of secondary wall) formation. This result indicates that mannan deposition was enhanced during secondary wall formation and mannan is present mainly in secondary wall.
The role of monolignol glucosides was also investigated by the feeding of radiolabeled coniferin and syringin into magnolia tree. It was suggested that syringin was not the direct precursor of lignin because of low concentration in lignifing tissues and grawing seasons. Microautoradiographic studies revealed that administered syringin was incorporated into cortex in the bark even in the non-lignifying season. While, coniferin was incorporated into the differentiating xylem and phloem fiber during the lignifing season, which indicated that coniferin is involved in the lignin biosynthesis.
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