Genetic Engineering of Cytokinins and Their Application to Agriculture

REFERENCES

• I. Abe, H. Tanaka, T. Abe, and H. Noguchi. (2007). Enzymatic formation of unnatural cytokinin analogs by adenylate isopentenyltransferase from mulberry. Biochem. Biophys. Res. Commun. 355:795–800.
   PubMed Web of Science ®Google Scholar
• W. M. Ainley, K. J. McNeil, J. W. Hill, R. B. Simpson, M. L. Brenner, R. T. Nagao, and J. L. Key. (1993). Regulatable endogenous production of cytokinins up to ‘toxic’ levels in transgenic plants and plant tissues. Plant Mol. Biol. 22:13–23.
   PubMed Web of Science ®Google Scholar
• D. E. Akiyoshi, H. Klee, R. M. Amasino, E. W. Nester, and P. M. Gordon. (1984). T-DNA of Agrobacterium tumefaciens encodes an enzyme of cytokinin biosynthesis. Proc. Nat. Acad. Sci. USA 81:5994–98.
   PubMed Web of Science ®Google Scholar
• A. Allavena, A. Giovannini, T. Berio, A. Spena, M. Zottini, G. P. Accotto, and A. M. Vaira. (2000). Genetic engineering of Osteospermum spp: a case story. The 19th International Symposium on Improvement of Ornamental Plants, Acta Horticulturae. 508:129–133.
   Google Scholar
• S. Ando, T. Asano, S. Tsushima, S. Kamachi, T. Hagio, and Y. Tabei. (2005). Changes in gene expression of putative isopentenyltransferase during clubroot development in Chinese cabbage (Brassica rapa L.). Physiol. Mol. Plant Pathol. 67:59–67.
   Web of Science ®Google Scholar
• M. Ashikari, H. Sakakibara, S. Lin, T. Yamamoto, T. Takashi, A. Nishimura, E. R. Angeles, Q. Qian, H. Kitano, and M. Matsuoka. (2005). Cytokinin oxidase regulates rice grain production. Science. 309:741–745.
   PubMed Web of Science ®Google Scholar
• F. Bai, and D. A. DeMason. (2008). Hormone interactions and regulation of PsPK2::GUS compared with DR5::GUS and PID::GUS in Arabidopsis thaliana. Amer. J. Bot. 95:133–145.
   PubMed Web of Science ®Google Scholar
• L. M. E. Balibrea, G. M. C. Gonzalez, T. Fatima, R. Ehness, T. K. Lee, R. Proels, W. Tanner, and T. Roitsch. (2004). Extracellular invertase is an essential component of cytokinin-mediated delay of senescence. Plant Cell 16:1276–1287.
   PubMed Web of Science ®Google Scholar
• G. F. Barry, S. G. Rogers, R. T. Fraley, and L. Brand. (1984). Identification of a cloned cytokinin biosynthetic gene. Proc. Nat. Acad. Sci. USA 81:4776–4780.
   PubMed Web of Science ®Google Scholar
• N. V. Bassil, D. W. S. Mok, and M. Mok. (1993). Partial purification of a cis-trans-isomerase of zeatin from immature seed of Phaseolus vulgaris L. Plant Physiol. 102:867–872.
   PubMed Web of Science ®Google Scholar
• R. L. Bell, R. Scorza, C. Srinivasan, and K. Webb. (1999). Transformation of “Beurre Bosc” pear with the rolC gene. J. Amer. Soc. Horticultural Sci. 124:570–574.
   Web of Science ®Google Scholar
• C. A. Beveridge. (2006). Axillary bud outgrowth: sending a message. Curr. Opin. Plant Biol 9 35–40.
   PubMed Web of Science ®Google Scholar
• C. A. Beveridge, U. Mathesius, R. J. Rose, and P. M. Gresshoff. (2007). Common regulatory themes in meristem development and whole-plant homeostasis. Curr. Opin. Plant Biol. 10:44–51.
   PubMed Web of Science ®Google Scholar
• K. D. Bilyeu, J. L. Cole, J. G. Laskey, W. R. Riekhof, T. J. Esparza, M. D. Kramer, and R. O. Morris. (2001). Molecular and biochemical characterization of a cytokinin oxidase from maize. Plant Physiol. 125:378–386.
   PubMed Web of Science ®Google Scholar
• M. R. Boase, C. S. Winefield, T. A. Lill, and M. J. Bendall. (2004). Transgenic regal pelargoniums that express the rolC gene from Agrobacterium rhizogenes exhibit a dwarf floral and vegetative phenotype. In Vitro Cellular Dev. Biol. 40:46–50.
   Web of Science ®Google Scholar
• A. Borochov, and W. R. Woodson. (1989). Physiology and biochemistry of flower petal senescence. Horticultural Rev. 11:15–43.
   Google Scholar
• J. S. Boyer. (1982). Plant productivity and environment. Science 218:443–448.
   PubMed Web of Science ®Google Scholar
• M. Carabelli, M. Possenti, G. Sessa, A. Ciolfi, M. Sassi, G. Morelli, and I. Ruberti. (2007). Canopy shade causes a rapid and transient arrest in leaf development through auxin-induced cytokinin oxidase activity. Genes Dev. 21:1863–1868.
   PubMed Web of Science ®Google Scholar
• H. Chang, M. L. Jones, G. M. Banowetz, and D. G. Clark. (2003). Overproduction of cytokinins in Petunia flowers transformed with PSAG12-IPT delays corolla senescence and decreases sensitivity to ethylene. Plant Physiol. 132:2174–2183.
   PubMed Web of Science ®Google Scholar
• F. Chefdor, H. Bénédetti, C. Depierreux, F. Delmotte, D. Morabito, and S. Carpin. (2006). Osmotic stress sensing in Populus: Components identification of a phosphorelay system. FEBS Lett. 580:77–81.
   PubMed Web of Science ®Google Scholar
• C. M. Chen, and D. K. Melitz. (1979). Cytokinin biosynthesis in a cell-free system from cytokinin-autotrophic tobacco tissue cultures. FEBS Lett. 107:15–20.
   PubMed Web of Science ®Google Scholar
• C. M. Chen, and S. M. Leisner. (1984). Modification of cytokinins by cauliflower microsomal enzymes. Plant Physiol. 75:442–46.
   PubMed Web of Science ®Google Scholar
• D. G. Clark, C. Dervinis, J. E. Barret, H. Klee, and M. Jones. (2004). Drought-induced leaf senescence and horticultural performance of transgenic PSAG12-IPT Petunias. J. Amer. Soc. Horticultural Sci. 129:93–99.
   Web of Science ®Google Scholar
• D. M. Connolly, and M. E. Winkler. (1991). Structure of Escherichia coli miaA and characterization of the mutator phenotype caused by miaA insertion mutation. J. Bacteriol. 173:1711–1721.
   PubMedGoogle Scholar
• I. S. Curtis, C. He, W. J. R. M. Jordi, E. Davelaar, J. B. Power, A. M. M. de Laat, and M. R. Davey. (1999). Promoter deletions are essential for transformation of lettuce by the T-cyt gene: The phenotypes of transgenic plants. Annals Bot. 83:559–567.
   Web of Science ®Google Scholar
• I. B. D'Agostino, and J. J. Kieber. (1999). Molecular mechanisms of cytokinin action. Curr. Opin. Plant Biol. 2:359–364.
   PubMed Web of Science ®Google Scholar
• J. T. Dietrich, M. Kaminek, D. G. Belvin, T. M. Beinbott, and R. O. Morris. (1995). Changes in cytokinins and cytokinin oxidase activity in developing maize kernels and the effects of exogenous cytokinin on kernel development. Plant Physiol. Biochem. 33:289–294.
   Web of Science ®Google Scholar
• Y. Ding, and Q. H. Ma. (2006). Biosynthesis, signal transduction, and molecular regulation of cytokinins. Curr. Pharma. Anal. 2:169–182.
   Web of Science ®Google Scholar
• I. C. Dodd, and C. A. Beveridge. (2006). Xylem-borne cytokinins: still in search of a role?. J. Exp. Bot. 57 1–4.
   PubMed Web of Science ®Google Scholar
• E. Dun, B. Ferguson, and C. A. Beveridge. (2006). Apical dominance and shoot branching: divergent opinions or divergent mechanisms. Plant Phys. 142:812–819.
   PubMed Web of Science ®Google Scholar
• J. J. Estruch, D. Chriqui, K. Grossmann, J. Schell, and A. Spena. (1991). The plant oncogene rolC is responsible for the release of cytokinins from glucoside conjugates. EMBO J. 10:2889–2895.
   PubMed Web of Science ®Google Scholar
• M. Faiss, M. Strnad, P. Redig, K. Dolzak, J. Hanus, H. Van Onckelen, and T. Schmiilling. (1996). Chemically induced expression of the rolC-encoded beta-glucuronidase in transgenic tobacco plants and analysis of cytokinin metabolism: RolC does not hydrolyze endogenous cytokinin glucosides in planta. Plant J. 10:33–46.
   Web of Science ®Google Scholar
• F. J. Ferreira, and J. J. Kieber. (2005). Cytokinin signaling. Curr. Opin. Plant Biol. 8:518–525.
   PubMed Web of Science ®Google Scholar
• E. Foo, S. E. Morris, K. Parmenter, N. Young, H. Wang, A. Jones, C. Rameau, C. G. N. Turnbull, and C. A. Beveridge. (2007). Feedback regulation of xylem cytokinin content is conserved in pea and Arabidopsis. Plant Physol. 143:1418–1428.
   PubMed Web of Science ®Google Scholar
• B. G. Forde. (2002). The role of long-distance signalling in plant responses to nitrate and other nutrients. J. Exp. Bot. 53:39–43.
   PubMed Web of Science ®Google Scholar
• J. M. Franco-Zorrilla, A. C. Martin, A. Leyva, and J. Paz-Ares. (2005). Interaction between phosphate-starvation, sugar, and cytokinin signaling in Arabidopsis and the roles of cytokinin receptors CRE1/AHK4 and AHK3. Plant Physol. 138:847–857.
   PubMed Web of Science ®Google Scholar
• Y. Fu, Y. Ding, X. Liu, C. Sun, S. Cao, D. Wang, S. He, X. Wang, L. Li, and W. Tian. (1998). Rice transformation with a senescence-inhibition chimeric gene. Chin. Sci. Bull. 43:1810–1815.
   Google Scholar
• P. Galuszka, J. Frebortova, T. Werner, M. Yamada, M. Strnad, T. Schmülling, and I. Frebort. (2004). Cytokinin oxidase/dehydrogen-ase genes in barley and wheat: Cloning and heterologous expression. Eur. J. Biochem. 271:3990–4002.
   PubMedGoogle Scholar
• S. Gan, and R. M. Amasino. (1997). Making sense of senescence: molecular genetic regulation of leaf senescence. Plant Physiol. 113:313–319.
   PubMed Web of Science ®Google Scholar
• S. Gan, and R. M. Amasino. (1995). Inhibition of leaf senescence by autoregulated production of cytokinin. Science 270:1986–1988.
   PubMed Web of Science ®Google Scholar
• R. Geurts, and T. Bisseling. (2002). Rhizobium Nod factor perception and signaling. Plant Cell 14:S239–S249.
   PubMed Web of Science ®Google Scholar
• S. Gonzalez-Rizzo, M. Crespi, and F. Frugier. (2006). The Medicago truncatula CRE1 cytokinin receptor regulates lateral root development and early symbiotic interaction with Sinorhizobium meliloti. Plant Cell 18:2680–2693.
   PubMed Web of Science ®Google Scholar
• K.-P. Gotz, N. Staroske, R. Radchuk, R. J. N. Emery, K.-D. Wutzke, H. Herzog, and H. Weber. (2007). Uptake and allocation of carbon and nitrogen in Vicia narbonensis plants with increased seed sink strength achieved by seed-specific expression of an amino acid permease. J. Exp. Bot. 58:3183–3195.
   Google Scholar
• J. Gray, J. Wang, and S. B. Gelvin. (1992). Mutation of the miaA gene of Agrobacterium tumefaciens results in reduced vir gene expression. J. Bacteriol. 174:1086–1098.
   PubMed Web of Science ®Google Scholar
• A. Guivarch, J. Rembur, M. Goetz, T. Roitsch, M. Noin, T. Schmülling, and D. Chriqui. (2002). Local expression of the ipt gene in transgenic tobacco (Nicotiana tabacum L. cv. SR1) axillary buds establishes a role for cytokinins in tuberization and sink formation. J. Exp. Bot. 53:621–629.
   PubMed Web of Science ®Google Scholar
• P. He, M. Osaki, M. Takebe, T. Shinano, and J. Wasaki. (2005). Endogenous hormones and expression of senescence-related genes in different senescent types of maize. J. Exp. Bot. 56:1117–1128.
   PubMed Web of Science ®Google Scholar
• A. Heyl, and T. Schmülling. (2003). Cytokinin signal perception and transduction. Curr. Opin. Plant Biol. 6:480–488.
   PubMed Web of Science ®Google Scholar
• T. J. V. Higgins, E. J. Newbegin, D. Spencer, D. J. Llewellyn, and S. Craig. (1988). The sequence of a pea vicilin gene and its expression in transgenic tobacco plants. Plant Mol. Biol. 11:683–695.
   PubMed Web of Science ®Google Scholar
• M. Higuchi, M. S. Pischke, A. P. Mahonen, K. Miyawaki, Y. Hashimoto, M. Seki, M. Kobayashi, K. Shinozaki, T. Kato, S. Tabata, Y. Helariutta, M. R. Sussman, and T. Kakimoto. (2004). In planta functions of the Arabidopsis cytokinin receptor family. Proc. Nat. Acad. Sci. USA 101:8821–8826.
   PubMed Web of Science ®Google Scholar
• N. Hirose, N. Makita, M. Kojima, T Kamada-Nobusada, and H Sakakibara. (2007). Overexpression of a type-A response regulator alters rice morphology and cytokinin metabolism. Plant Cell Physiol. 48:523–539.
   Google Scholar
• N. Hirose, K. Takei, T. Kuroha, T. Kamada-Nobusada, H Hayashi, and H. Sakakibara. (2008). Regulation of cytokinin biosynthesis, compartmentalization and translocation. J. Exp. Bot. 59:75–83.
   PubMed Web of Science ®Google Scholar
• N. Houba-Hérin, C. Pethe, J. d'Alayer, and M. Laloue. (1999). Cytokinin oxidase from Zea mays: Purification, cDNA cloning and expression in moss protoplasts. Plant J. 17:615–626.
   PubMed Web of Science ®Google Scholar
• L. N. Huynh, T. Van Toai, J. Streeter, and G. Banowetz. (2005). Regulation of flooding tolerance of SAG12:ipt Arabidopsis plants by cytokinin. J. Exp. Bot. 56:1397–1407.
   PubMed Web of Science ®Google Scholar
• A. Imamura, N. Hanaki, A. Nakamura, T. Suzuki, M. Taniguchi, T. Kiba, C. Ueguchi, T. Sugiyama, and T. Mizuno. (1999). Compilation and characterization of Arabidopsis thaliana response regulators implicated in His-Asp phosphorelay signal transduction. Plant Cell Physiol. 40:733.
   PubMed Web of Science ®Google Scholar
• T. Inoue, M. Higuchi, Y. Hashimoto, M. Seki, M. Kobayashi, T. Kato, S. Tabata, K. Shinozaki, and T. Kakimoto. (2001). Identification of CRE1 as a cytokinin receptor from Arabidopsis. Nature 409:1060–1063.
   PubMed Web of Science ®Google Scholar
• K. Ishida, T. Yamashino, A Yokoyama, and T. Mizuno. (2008). Three type-B response regulators, ARR1, ARR10 and ARR12, play essential but redundant roles in cytokinin signal transduction throughout the life cycle of Arabidopsis thaliana. Plant Cell Physiol. 49:47–57.
   PubMed Web of Science ®Google Scholar
• R. J. Jones, and B. M. N. Schreiber. (1997). Role and function of cytokinin oxidase in plants. Plant Growth Regul. 23:123–134.
   Web of Science ®Google Scholar
• W. Jordi, A. Schapendonk, E. Davelaar, G. M. Stoopen, C. S. Pot, R. De Visser, J. A. Van Rhijn, S. Gan, and R. M. Amasino. (2000). Increased cytokinin levels in transgenic P-SAG12-IPT tobacco plants have large direct and indirect effects on leaf senescence, photosynthesis and N partitioning. Plant, Cell Environ. 23:279–289.
   Web of Science ®Google Scholar
• T. Kakimoto. (1996). CKI1, a histidine kinase homolog implicated in cytokinin signal transduction. Science 274:982–985.
   PubMed Web of Science ®Google Scholar
• T. Kakimoto. (2001). Identification of plant cytokinin biosynthetic enzymes as dimethylallyl diphosphate: ATP/ADP isopentenyl transferases. Plant Cell Physiol. 42:677–685.
   PubMed Web of Science ®Google Scholar
• M. Kaminek. (1992). Progress in cytokinin research. Trends Biotechnol. 10:159–164.
   Web of Science ®Google Scholar
• J. Kaneyoshi, and S. Kobayashi. (1999). Characteristics of transgenic trifoliate orange (Poncirus trifoliata Raf.) possessing the rolC gene of Agrobacterium rhizogenes Ri plasmid. J. Japanese Soc. Horticultural Sci. 68:734–738.
   Google Scholar
• M. Khodakovskaya, Y. Li, J. Li, R. Vankova, J. Malbeck, and R. McAvoy. (2005). Effects of cor15a-IPT gene expression on leaf senescence in transgenic Petunia x hybrida and Dendranthema x grandiflorum. J. Exp. Bot. 56:1165–1175.
   PubMed Web of Science ®Google Scholar
• H. J. Kim, H. Ryu, S. H. Hong, H. R. Woo, P. O. Lim, I. C. Lee, J. Sheen, H. G. Nam, and I. Hwang. (2006). Cytokinin-mediated control of leaf longevity by AHK3 through phosphorylation of ARR2 in Arabidopsis. Proc. Nat. Acad. Sci. USA 103:814–819.
   PubMed Web of Science ®Google Scholar
• Y. Koshita, Y. Nakamura, S. Kobayashi, and K. Morinaga. (2002). Introduction of the rolC gene into the genome of the Japanese persimmon causes dwarfism. J. Japanese Soc. Horticultural Sci. 71:529–531.
   Google Scholar
• T. Kurakawa, N. Ueda, M. Maekawa, K. Kobayashi, M. Kojima, Y. Nagato, H. Sakakibara, and J. Kyozuka. (2007). Direct control of shoot meristem activity by a cytokinin-activating enzyme. Nature 445:652–655.
   PubMed Web of Science ®Google Scholar
• D. Lee, and E. Natesan. (2006). Evaluating genetic containment strategies for transgenic plants. Trends Biotechnol. 24:109–114.
   PubMed Web of Science ®Google Scholar
• D. S. Letham. (1963). Zeatin, a factor inducing cell division from Zea mays. Life Sci. 8:569–573.
   Google Scholar
• D. S. Letham, and L. M. S. Palni. (1983). Cytokinin metabolism and biosynthesis. Ann. Rev. Plant Physiol. 34:163–197.
   Google Scholar
• Q. Li, P. R. H. Robson, A. J. E. Bettany, I. S. Donnison, H. Thomas, and I. M. Scott. (2004). Modification of senescence in ryegrass transformed with IPT under the control of a monocot senescence-enhanced promoter. Plant Cell Rep. 22:816–821.
   PubMed Web of Science ®Google Scholar
• X. Li, Q. Qian, Z. Fu, Y. Wang, G. Xiong, D. Zeng, X. Wang, X. Liu, S. Teng, F. Hiroshi, M. Yuan, D. Luok, B. Han, and J. Li. (2003). Control of tillering in rice. Nature 422:618–621.
   PubMed Web of Science ®Google Scholar
• J Lopez-Bucio, M. Millan-Godinez, A. Mendez-Bravo, A. Morquecho-Contreras, E. Ramirez-Chavez, J. Molina-Torres, A. Perez-Torres, M. Higuchi, T. Kakimoto, and L. Herrera-Estrella. (2007). Cytokinin receptors are involved in alkamide regulation of root and shoot development in Arabidopsis. Plant Physiol. 145:1703–1713.
   PubMed Web of Science ®Google Scholar
• Q. H. Ma, Z. B. Lin, and D. Z. Fu. (2002). Increased seed cytokinin levels in transgenic tobacco influence embryo and seedling development. Funct. Plant Biol. 29:1107–1113.
   PubMed Web of Science ®Google Scholar
• Q. H. Ma, and Y. R. Song. (1993). Genetic engineering of plant hormones. Acta Bot. Sinica. 35:18–28.
   Google Scholar
• Q. H. Ma, and B. Tian. (2005). Characterization of a wheat histidine-containing phosphotransfer protein (HP) that is regulated by cytokinin-mediated inhibition of leaf senescence. Plant Sci. 168:1507–1514.
   Web of Science ®Google Scholar
• Q. H. Ma, X. M. Wang, and Z. M. Wang. (2008). Expression of isopentenyl transferase gene controlled by seed-specific lectin promoter in transgenic tobacco influences seed development. J. Plant Growth Regul. 27:68–76.
   Web of Science ®Google Scholar
• Q. H. Ma, R. Zhang, C. H. Hocart, D. S. Letham, and T. J. V. Higgins. (1998). Seed-specific expression of the isopentenyl transferase gene (ipt) in transgenic tobacco. Aust. J. Plant Physiol. 25:53–59.
   Google Scholar
• A. P. Mahonen, A. Bishopp, M. Higuchi, K. M. Nieminen, K. Kinoshita, K. Tormakangas, Y. Ikeda, A. Oka, T. Kakimoto, and Y. Helariutta1. (2006). Cytokinin signaling and its inhibitor AHP6 regulate cell fate during vascular development. Science 311:94–97.
   PubMed Web of Science ®Google Scholar
• M. S. McCabe, L. Garratt, F. Schepers, W. J. R. M. Jordi, G. M. Stoopen, E. Davelaar, J. H. A. van Rhijn, J. B. Power, and M. Davey. (2001). Effects of PSAG12-IPT gene expression on development and senescence in transgenic lettuce. Plant Physiol. 127:505–516.
   PubMed Web of Science ®Google Scholar
• R. C. Martin, M. C. Mok, J. E. Habben, and D. W. S. Mok. (2001). A maize cytokinin gene encoding an O-glucosyltransferase specific to cis-zeatin. Proc. Nat. Acad. Sci. USA 98:5922–5926.
   PubMed Web of Science ®Google Scholar
• B. Martineau, C. M. Houck, R. E. Sheehy, and W. R. Hiatt. (1994). Fruit-specific expression of the A. tumefaciens isopentenyl transferase gene in tomato: effects on fruit ripening and defence-related gene expression in leaves. Plant J. 5:11–19.
   Web of Science ®Google Scholar
• B. Martineau, K. R. Summerfelt, D. F. Adams, and J. W. Deverma. (1995). Production of high solid tomatoes through molecular modification of levels of the plant growth regulator cytokinin. Bio/Technology 13:250–254.
   Web of Science ®Google Scholar
• A. Massonneau, N. Houba-Herin, C. Pethe, C. Madzak, M. Falque, M. Mercy, D. Kopecny, A. Majira, P. Rogowsky, and M. Laloue. (2004). Maize cytokinin oxidase genes: differential expression and cloning of two new cDNAs. J. Exp. Bot. 55:2549–2557.
   PubMed Web of Science ®Google Scholar
• L. J. Matthews, R. O. Morris, and D. G. Blevins. (1992). Genetic mechanisms for Rhizobium cytokinin biosynthesis, and their relationship to nodule development. Plant Physiol. 99 (suppl):37.
   Google Scholar
• P. Maul, M. Bausher, G. McCollum, J. Mozoruk, and R. Niedz. (2006). CsHPt1, a putative histidine-containing phosphotransmitter protein induced during early somatic embryogenesis in Valencia sweet orange. Plant Sci. 170:44–53.
   Web of Science ®Google Scholar
• C. O. Miller, F. Skoog, M. H. von Saltza, and F. Strong. (1955). Kinetin, a cell division factor from deoxyribonucleic acid. J. Amer. Chem. Soc. 77:1392.
   Web of Science ®Google Scholar
• T. Y. Mitiouchkina, and S. V. Dolgov. (2000). Modification of chrysanthemum flower and plant architecture by rolC gene from Agrobacterium rhizogenes introduction. The 19th International Symposium on Improvement of Ornamental Plants, Acta Horticulturae. 508:163–169.
   Google Scholar
• K. Miyawaki, P. Tarkowski, M. Matsumoto-Kitano, T. Kato, S. Sato, D. Tarkowska, S. Tabata, G. Sandberg, and T. Kakimoto. (2006). Roles of Arabidopsis ATP/ADP isopentenyltransferases and tRNA isopentenyltransferases in cytokinin biosynthesis. Proc. Nat. Acad. Sci. USA 103:16598–16603.
   PubMed Web of Science ®Google Scholar
• D. W. Mok, and M. C. Mok. (2001). Cytokinin metabolism and action. Annual Review Plant Physiol. Plant Mol. Biol. 52:89–118.
   PubMed Web of Science ®Google Scholar
• R. O. Morris, K. D. Bilyeu, J. G. Laskey, and N. N. Cheikh. (1999). Isolation of a gene encoding a glycosylated cytokinin oxidase from maize. Biochem. Biophys. Res. Commun. 255:328–333.
   PubMed Web of Science ®Google Scholar
• G. C. Morris, T. Mirunalni, and D. Kim. (2006). A possible role of cytokinin in mediating long-distance nitrogen signaling in the promotion of sylleptic branching in hybrid poplar. J. Plant Physiol. 163:684–68.
   PubMed Web of Science ®Google Scholar
• B. Müller, and J. Sheen. (2007). Advances in cytokinin signaling. Science 318:68–69.
   PubMed Web of Science ®Google Scholar
• J. D. Murray, B. J. Karas, S. Sato, S. Tabata, L. Amyot, and K. Szczyglowski. (2007). A cytokinin perception mutant colonized by Rhizobium in the absence of nodule organogenesis. Science 315:101–104.
   PubMed Web of Science ®Google Scholar
• H. G. Nam. (1997). The molecular genetic analysis of leaf senescence. Curr. Opin. Biotechnol. 8:200–207.
   PubMed Web of Science ®Google Scholar
• O. Nilsson, T. Moritz, B. Sundberg, G. Sandberg, and O. Olsson. (1996). Expression of the Agrobacterium rhizogenes rolC gene in a deciduous forest tree alters growth and development and leads to stem fasciation. Plant Physiol. 112:493–502.
   PubMed Web of Science ®Google Scholar
• A. Nordstrom, P. Tarkowski, D. Tarkowska, R. Norbaek, C. Åstot, K. Dolezal, and G. Sandberg. (2004). Auxin regulation of cytokinin biosynthesis in Arabidopsis thaliana. A factor of potential importance for auxin–cytokinin-regulated development. Proc. Nat. Acad. Sci. USA 101:8039–8044.
   PubMed Web of Science ®Google Scholar
• S. A. Oh, J. H. Park, G. I. Lee, K. H. Paek, S. K. Park, and G. N. Hong. (1997). Identification of three genetic loci controlling leaf senescence in Arabidopsis thaliana. Plant J. 12:527–535.
   PubMed Web of Science ®Google Scholar
• A. Oka. (2003). New insights into cytokinins. J. Plant Res. 116:217–220.
   PubMed Web of Science ®Google Scholar
• V Ongaro, and O. Leyser. (2008). Hormonal control of shoot branching. J. Exp. Bot. 59:67–74.
   PubMed Web of Science ®Google Scholar
• N. Papon, A. Oudin, A. Vansiri, M. Rideau, J. C. Chénieux, and J. Crèche. (2003). Differential expression of two type-A response regulators in plants and cell cultures of Catharanthus roseus (L.) G. Don. J. Exp. Bot. 54:1793–1795.
   PubMed Web of Science ®Google Scholar
• N. Papon, A. Vansiria, P. Ganteta, J. C. Chenieux, M. Rideau, and J. Creche. (2004). Histidine-containing phosphotransfer domain extinction by RNA interference turns off a cytokinin signalling circuitry in Catharanthus roseus suspension cells. FEBS Lett. 558:85–88.
   PubMed Web of Science ®Google Scholar
• A. N. Pepper, A. P. Morse, and F. C. Guinel. (2007). Abnormal root and nodule vasculature in R50 (sym16), a pea nodulation mutant which accumulates cytokinins. Annals Bot. 99:765–776.
   PubMed Web of Science ®Google Scholar
• M. Pogány, J. Koehl, I. Heiser, E. F. Elstner, and B. Barna. (2004). Juvenility of tobacco induced by cytokinin gene introduction decreases susceptibility to Tobacco necrosis virus and confers tolerance to oxidative stress. Physiol. Mol. Plant Pathol. 65:39–47.
   Web of Science ®Google Scholar
• H. Popelková, P. Galuszka, J. Frébortová, K. D. Bilyeu, and I. Frébort. Cytokinin dehydrogenase: characterization and structure homology modeling of the flavoprotein catabolizing plant hormones cytokinins. Recent Research Developments in ProteinsS. G. Pandalai. Transworld Research Network, KeralaIndia, (2004) 263–81.
   Google Scholar
• L. Reiser, P. Sanchez-Baracaldo, and S. Hake. (2000). Knots in the family tree: evolutionary relationships and functions of knox homeobox genes. Plant Mol. Biol. 42:151–166.
   PubMed Web of Science ®Google Scholar
• M. Riefler, O. Novak, M. Strnad, and T. Schmülling. (2006). Arabidopsis cytokinin receptor mutants reveal functions in shoot growth, leaf senescence, seed size, germination, root development, and cytokinin metabolism. Plant Cell 18:40–54.
   PubMed Web of Science ®Google Scholar
• R. M. Rivero, M. Kojima, A. Gepstein, H. Sakakibara, R. Mittler, S. Gepstein, and E. Blumwald. (2007). Delayed leaf senescence induces extreme drought tolerance in a flowering plant. Proc. Nat. Acad. Sci. USA 104:19631–19636.
   PubMed Web of Science ®Google Scholar
• P. R. H. Robson, I. S. Donnison, K. Wang, B. Frame, S. E. Pegg, A. Thomas, and H. Thomas. (2004). Leaf senescence is delayed in maize expressing the Agrobacterium IPT gene under the control of a novel maize senescence-enhanced promoter. Plant Biotechnol. J. 2:101–112.
   PubMed Web of Science ®Google Scholar
• P. Roeckel, T. Oancia, and J. Drevet. (1997). Effects of seed-specific expression of a cytokinin biosynthetic gene on canola and tobacco phenotypes. Transgenic Res. 6:133–141.
   PubMed Web of Science ®Google Scholar
• H. Rolletschek, F. Hosein, M. Miranda, U. Heim, K. P. Gotz, A. Schlereth, L. Borisjuk, I. Saalbach, U. Wobus, and H. Weber. (2005). Ectopic expression of an amino acid transporter (VfAAP1) in seeds of Vicia narbonensis and Pisum sativum increases storage proteins. Plant Physiol. 137:1236–1249.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara. (2003). Nitrate-specific and cytokinin-mediated nitrogen signaling pathways in plants. J. Plant Res. 116:253–257.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara, A. Hayakawa, A. Deji, S. Gawronski, and T. Sugiyama. (1999). His-Asp phosphotransfer possibly involved in a nitrogen signal transduction mediated by cytokinin in maize: molecular cloning of cDNAs for two-component regulatory factors and demonstration of phosphotransfer activity in vitro. Plant Mol. Biol. 41:563–573.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara, H. Kasahara, N. Ueda, M. Kojima, K. Takei, S. Hishiyama, T. Asami, K. Okada, Y. Kamiya, T. Yamaya, and S. Yamaguchi. (2005). Agrobacterium tumefaciens increases cytokinin production in plastids by modifying the biosynthetic pathway in the host plant. Proc. Nat. Acad. Sci. USA 102:9972–9977.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara, M. Suzuki, K. Takei, A. Deji, M. Taniguchi, and T. Sugiyama. (1998). A response-regulator homologue possibly involved in nitrogen signal transduction mediated by cytokinin in maize. Plant J. 14:337–344.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara, and K. Takei. (2002). Identification of cytokinin biosynthesis genes in Arabidopsis: A breakthrough for understanding the metabolic pathway and the regulation in higher plants. J. Plant Growth Regul. 21:17–23.
   PubMed Web of Science ®Google Scholar
• H. Sakakibara, K. Takei, and N. Hirose. (2006). Interactions between nitrogen and cytokinin in the regulation of metabolism and development. Trends Plant Sci. 11:440–448.
   PubMed Web of Science ®Google Scholar
• T. Sakamoto, H. Sakakibara, M. Kojima, Y. Yamamoto, H. Nagasaki, Y. Inukai, Y. Sato, and M. Matsuoka. (2006). Ectopic expression of KNOTTED1-like homeobox protein induces expression of cytokinin biosynthesis genes in rice. Plant Physiol. 142:54–62.
   PubMed Web of Science ®Google Scholar
• Y. Sakano, Y. Okada, A. Matsunaga, T. Suwama, T. Kaneko, K. Ito, H. Noguchi, and I. Abe. (2004). Molecular cloning, expression, and characterization of adenylate isopentenyltransferase from hop (Humulus lupulus L.). Phytochemistry 65:2439–2446.
   PubMed Web of Science ®Google Scholar
• J. Sheen. (2002). Phosphorelay and transcription control in cytokinin signal transduction. Science 296:1650–1652.
   PubMed Web of Science ®Google Scholar
• H. E. Schroeder. (1984). Effects of applied growth regulators on pod growth and seed protein composition in Pisum sativum L. J. Exp. Bot. 35:813–821.
   Web of Science ®Google Scholar
• T. Schmülling, J. Schell, and A. Spena. (1988). Single genes from Agrobacterium rhizogenes influence plant development. EMBO J. 7:2621–2629.
   PubMed Web of Science ®Google Scholar
• S. H. Schwartz, X. Qin, and M. C. Loewen. (2004). The Biochemical characterization of two carotenoid cleavage enzymes from Arabidopsis indicates that a carotenoid-derived compound inhibits lateral branching. J. Biol. Chem. 279:46940–46945.
   PubMed Web of Science ®Google Scholar
• R. Scorza, T. W. Zimmerman, J. M. Cordts, K. J. Footen, and M. Ravelonandro. (1994). Horticultural characteristics of transgenic tobacco expressing the rolC gene from Agrobacterium rhizogenes. J. Amer. Soc. Horticultural Sci. 119:1091–1098.
   Web of Science ®Google Scholar
• J. Stougaard. (2000). Regulators and regulation of legume root nodule development. Plant Physiol. 124:531–540.
   PubMed Web of Science ®Google Scholar
• T. Suzuki, A. Imamura, C. Ueguchi, and T. Mizuno. (1998). Histidine-containing phosphotransfer (HPt) signal transducers implicated in His-to-Asp phosphorelay in Arabidopsis. Plant Cell Physiol. 39:1258–1268.
   PubMed Web of Science ®Google Scholar
• T. Suzuki, K. Sakurai, A. Imamura, A. Nakamura, C. Ueguchi, and T. Mizuno. (2000). Compilation and characterization of Histidine-containing phosphotransmitters implicated in His-to-Asp phosphorelay in plants: AHP signal transducers of Arabidopsis thaliana. Biosci., Biotechnol. Biochem. 64:2486–2489.
   PubMed Web of Science ®Google Scholar
• K. Takei, H. Sakakibara, and T. Sugiyama. (2001). Identification of genes encoding adenylate isopentenyl-transferase, a cytokinin biosynthesis enzyme, in Arabidopsis. thaliana.. J. Biol. Chem. 276 26405–26410.
   PubMed Web of Science ®Google Scholar
• K. Takei, H. Sakakibara, M. Taniguchi, and T. Sugiyama. (2001). Nitrogen-dependent accumulation of cytokinins in root and the translocation to leaf: Implication of cytokinin species that induces gene expression of maize response regulator. Plant Cell Physiol. 42:85–93.
   PubMed Web of Science ®Google Scholar
• K. Takei, T. Yamaya, and H. Sakakibara. (2004). Arabidopsis CYP735A1 and CYP735A2 encode cytokinin hydroxylases that catalyze the biosynthesis of trans-zeatin. J. Biol. Chem. 279:41866–41872.
   PubMed Web of Science ®Google Scholar
• K. Takei, N. Ueda, K. Aoki, T. Kuromori, T. Hirayama, K. Shinozaki, T. Yamaya, and H. Sakakibara. (2004). AtIPT3 is a key determinant of nitrate-dependent cytokinin biosynthesis in Arabidopsis.. Plant Cell Physiol. 45 1053–1062.
   PubMed Web of Science ®Google Scholar
• Y. Taya, Y. Tanaka, and S. Nishimura. (1978). 5′-AMP is a direct precursor of cytokinin in Dictyostelium discoidum. Nature 271:545–54.
   PubMed Web of Science ®Google Scholar
• L. Tirichine, N. Sandal, L. H. Madsen, S. Radutoiu, A. S. Albrektsen, S. Sato, E. Asamizu, S. Tabata, and J. Stougaard. (2007). A gain-of-function mutation in a cytokinin receptor triggers spontaneous root nodule organogenesis. Science 315:104–107.
   Google Scholar
• L. P. Tran, T. Urao, F. Qin, K. Maruyama, T. Kakimoto, K. Shinozaki, and K. Yamaguchi-Shinozaki. (2007). Functional analysis of AHK1/ATHK1 and cytokinin receptor histidine kinases in response to abscisic acid, drought, and salt stress in Arabidopsis. Proc. Nat. Acad. Sci. USA 104:20623–20628.
   PubMed Web of Science ®Google Scholar
• C. Ueguchi, H. Koizumi, T. Suzuki, and T. Mizuno. (2001). Novel family of sensor histidine kinase genes in Arabidopsis thaliana. Plant Cell Physiol. 42:231–235.
   PubMed Web of Science ®Google Scholar
• J. Van Staden, and F. E. Drewes. (1993). Incorporation of [8–14C]adenine into pea fruits. J. Plant Physiol. 141:380–382.
   Web of Science ®Google Scholar
• T. T. Van Toai, P. Saglio, B. Ricard, and A. Pradet. (1995). Developmental regulation of anoxic stress tolerance in maize. Plant, Cell Environ. 18:937–942.
   Web of Science ®Google Scholar
• I. K. Vasil. (2005). The story of transgenic cereals: the challengen, the debate, and the solution—A historical perspective. In Vitro Plant 41:577–583.
   Web of Science ®Google Scholar
• Y. K. Veach, R. C. Martin, D. W. S. Mok, J. Malbeck, R. Vankova, and M. C. Mok. (2003). O-Glucosylation of cis-zeatin in maize. Characterization of genes, enzymes, and endogenous cytokinins. Plant Physiol. 131:1374–1380.
   PubMed Web of Science ®Google Scholar
• T. Werner, V. Motyka, V. Laucou, R. Smets, H. Van Onckelen, and T. Schmülling. (2003). Cytokinin-deficient transgenic Arabidopsis plants show multiple developmental alterations indicating opposite functions of cytokinins in the regulation of shoot and root meristem activity. Plant Cell 15:2532–2550.
   PubMed Web of Science ®Google Scholar
• T. Werner, V. Motyka, M. Strnad, and T. Schmülling. (2001). Regulation of plant growth by cytokinin. Proc. Nat. Acad. Sci. USA 98:10487–10492.
   PubMed Web of Science ®Google Scholar
• C. Winefield, D. Lewis, S. Arathoon, and S. Deroles. (1999). Alterations of Petunia plant form through the introduction of the rolC gene from Agrobacterium rhizogenes. Mol. Breed. 5:543–551.
   Web of Science ®Google Scholar
• F. F. White, B. H. Taylor, G. A. Huffman, M. P. Gordon, and E. W. Nester. (1985). Molecular and genetic analysis of the transferred DNA regions of the root-inducing plasmid of Agrobacterium rhizogenes. J. Bacteriol. 164:33–44.
   PubMed Web of Science ®Google Scholar
• S. H. Yang, H. Yu, and C. J. Goh. (2003). Functional characterisation of a cytokinin oxidase gene DSCKX1 in Dendrobium orchid. Plant Mol. Biol. 51:237–248.
   PubMed Web of Science ®Google Scholar
• C. J. Ye, S. W. Wu, F. N. Kong, C. J. Zhou, Q. K. Yang, Y. Sun, and B. Wang. (2006). Identification and characterization of an isopentenyltransferase (IPT) gene in soybean (Glycine max L.). Plant Sci. 170:542–550.
   Web of Science ®Google Scholar
• A. Yokoyama, T. Yamashino, Y. Amano, Y. Tajima, A. Imamura, H. Sakakibara, and T Mizuno. (2007). Type-B ARR transcription factors, ARR10 and ARR12, are implicated in cytokinin-mediated regulation of protoxylem differentiation in roots of Arabidopsis thaliana. Plant Cell Physiol. 48:84–96.
   PubMed Web of Science ®Google Scholar
• T. E. Young, J. Giesler-Lee, and D. R. Gallie. (2004). Senescence-induced expression of cytokinin reverses pistil abortion during maize flower development. Plant J. 38:910–922.
   Google Scholar
• J. Zhang, T. Van Toai, L. Huynh, and J. Preiszner. (2000). Development of flooding-tolerant Arabidopsis thaliana by autoregulated cytokinin production. Mol. Breed. 6:135–144.
   Web of Science ®Google Scholar
• E. Zubko, C. J. Adams, I. Macháèková, J. Malbeck, C. Scollan, and P. Meyer. (2002). Activation tagging identifies a gene from Petunia hybrida responsible for the production of active cytokinins in plants. Plant J. 29:797–808.
   PubMed Web of Science ®Google Scholar
• A. Zuker, T. Tzfira, G. Scovel, M. Ovadis, E. Shklarman, H. Itzhaki, and A. Vainstein. (2001). rolC-transgenic carnation with improved agronomic traits: Quantitative and qualitative analyses of greenhouse-grown plants. J. Amer. Soc. Horticultural Sci. 126:13–18.
   Web of Science ®Google Scholar