TY - JOUR
T1 - Reproductive organs regulate leaf nitrogen metabolism mediated by cytokinin signal
AU - Igarashi, Daisuke
AU - Izumi, Yoshihiro
AU - Dokiya, Yuko
AU - Totsuka, Kazuhiko
AU - Fukusaki, Eiichiro
AU - Ohsumi, Chieko
N1 - Funding Information:
Acknowledgments Part of this work was performed in the project ‘‘Development of Fundamental Technologies for Controlling the Production of Industrial Materials by Plants,’’ which was supported by the New Energy and Industrial Technology Development Organization (NEDO), Japan. The authors are grateful to Tatsuo Kakimoto (Osaka University, Japan) for providing the knockout plants and helpful discussions and to Tsuyoshi Nakagawa (Shimane University, Japan) for providing the Gateway plasmid for reporter gene assay. We also thank Kiyoshi Miwa, Akira Mitsui, Hiroyuki Kiyohara, and Ryoko Nagasaka for their helpful discussions and technical assistance.
PY - 2009/2
Y1 - 2009/2
N2 - The metabolism of vegetative organs in plants changes during the development of the reproductive organs. The regulation of this metabolism is important in the control of crop productivity. However, the complexity of the regulatory systems makes it difficult to elucidate their mechanisms. To examine these mechanisms, we constructed model experiments using Arabidopsis to analyze metabolic and gene expression changes during leaf-stage progression and after removal of the reproductive organs. Leaf gene expression levels and content of major amino acids, both of which decreased during leaf-stage progression, increased after removal of the reproductive organs. In particular, the levels of expression of cytokinin biosynthesis genes and cytokinin-responsive genes and the cytokinin content increased after removal of the reproductive organs. Analysis of plants with knockout of a cytokinin-biosynthetic gene (AtIPT3) and a cytokinin receptor gene (AHK3) indicated that glutamate dehydrogenase genes (GDH3) were regulated by cytokinin signaling. These data suggest that cytokinins regulate communication between reproductive and vegetative organs, and that GDH3 is one target of the cytokinin-mediated regulation of nitrogen metabolism.
AB - The metabolism of vegetative organs in plants changes during the development of the reproductive organs. The regulation of this metabolism is important in the control of crop productivity. However, the complexity of the regulatory systems makes it difficult to elucidate their mechanisms. To examine these mechanisms, we constructed model experiments using Arabidopsis to analyze metabolic and gene expression changes during leaf-stage progression and after removal of the reproductive organs. Leaf gene expression levels and content of major amino acids, both of which decreased during leaf-stage progression, increased after removal of the reproductive organs. In particular, the levels of expression of cytokinin biosynthesis genes and cytokinin-responsive genes and the cytokinin content increased after removal of the reproductive organs. Analysis of plants with knockout of a cytokinin-biosynthetic gene (AtIPT3) and a cytokinin receptor gene (AHK3) indicated that glutamate dehydrogenase genes (GDH3) were regulated by cytokinin signaling. These data suggest that cytokinins regulate communication between reproductive and vegetative organs, and that GDH3 is one target of the cytokinin-mediated regulation of nitrogen metabolism.
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U2 - 10.1007/s00425-008-0858-2
DO - 10.1007/s00425-008-0858-2
M3 - Article
C2 - 19048287
AN - SCOPUS:59449102490
SN - 0032-0935
VL - 229
SP - 633
EP - 644
JO - Planta
JF - Planta
IS - 3
ER -