1993 Fiscal Year Final Research Report Summary
The Regulation of Photosynthesis and Nitrogen Assimilation Genes by Nitrogen in C4 Plants
| Project/Area Number |
04454072
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
応用生物化学・栄養化学
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| Research Institution | NAGOYA UNIVERSITY |
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Principal Investigator |
SUGIYAMA Tatsuo Nagoya University, School of Agricultural Sciences, Department of Applied Biological Sciences Professor, 農学部, 教授 (50023453)
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| Co-Investigator(Kenkyū-buntansha) |
TANIGUCHI Mitsutaka Nagoya University, School of Agricultural Sciences, Department of Applied Biolog
SAKAKIBARA Hitoshi Nagoya University, School of Agricultural Sciences, Department of Applied Biolog
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| Project Period (FY) |
1992 – 1993
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| Keywords | Maize (Zea mays) / Panicum miliaceum / phosphoenolphruvate carboxylase / Carbon assimilation / Nitrogen assimilation / Regulation of gene expression by nitrogen / C4-photosynthesis / Cytokinin |
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| Research Abstract |
(1)The nitrate-inducible transcription of genes for nitrate reductase (NR), plastidic glutamine synthetase (GS2), and ferredoxin-glutamate synthase (Fd-GOGAT) is transient and precedes the gene transcription for phosphoenolpyruvate carboxylase (C4-PEPC) in maize mesophyll cells.(2)The nitrogen-inducible accumulation of mRNAs for PEPC and carbonic anhydrase (CA) requires cytokinin and glutamine as positive signals ; cytokinin up-regulates their transcription and glutamine up-regulates the accumulation of their mRNAs.(3)The cytokinin-dependent transcription of C4-PEPC requires the synthesis of protein(s) and the accumulation of C4-PEPC mRNA appears to be mediated by protein kinase and protein phosphatase activities, whereas the accumulation of mRNAs for NR and GS2 does not require the synthesis of protein.(4)The nitrogen-inducible accumulation of mRNAs for NR, GS2, and Fd-GOGAT does not requite cytokinin and glutamine acts as a negative signal for the accumulation of NR mRNA.It was suggested that protein phosphatase activity involves in the nitrate-dependent accumulation of mRNAs for NR and GS2.(5)Aspartate aminotransferase genes in Panicun miliaceum, an NAD-ME type of C4-plant, were cloned and sequenced. The gene expression of the isozyme which is located in the mesophyll cells was found to be selectively regulatee by nitrogen-availability.
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