Molecular mechanism of flexible development and differentiation in plants

植物生长的分子机制研究我们鉴定了赤霉素（giberellin， GA）受体。这是一种重要的生长激素。gaa受体在合理浓度下与生物活性GAs相互作用。GA与受体的结合诱导GID1与DELLA蛋白之间的相互作用，而DELLA蛋白是GA信号传导的负向因子。细胞分裂素是另一种生长植物激素。我们鉴定了三个编码细胞分裂素受体的基因，并研究了它们在植物功能中的相关性。我们还发现水稻的粒数受花分生组织中细胞分裂素水平的控制。利用粒数基因，提高了日本顶级水稻主导品种光光的粒数。我们确定了一组被称为PRRs的成分（或基因），它们在拟南芥生物钟中起着协调的重要作用（或剂量），对植物开花时间的控制很重要。我们还发现了一种植物肽激素受体pktosulfokine。〇植物对自然环境响应的分子机制研究我们发现了5种水稻阳离子/氢离子交换剂的特征性质。Ktr/HKTtype转运体对于植物和细菌适应盐度胁迫和高渗透压也至关重要。我们还发现硝酸盐转运基因被多种涉及硝酸盐和/或亚硝酸盐的机制激活，并且谷氨酰胺被证明在转录和翻译后水平上调节硝酸盐转运活性。为了了解高渗应激反应的信号转导，我们已经确定了一个SnRK2相互作用蛋白，它可以作为信号传导成分的支架。

○Study on molecular mechanism of plant growthWe identified a receptor of gibberellin (GA). which is an important growth phytohormone. The GAreceptor interacts with bioactive GAs at a reasonable concentration. The binding GA to the receptor induces the interaction between GID1 and a DELLA protein, which functions as a negative factor of GA signaling. Cytokinin is another growth phytohomone. We identified the three genes encoding cytokinin receptors and investigated their relevant in planta functions. We also revealed that a grain number in rice is controlled by the level of cytokinin in the floral meristems. Using the graining number gene, we increased the grain number of Koshihikari, the top rice leading variety of Japan. We identified a set of components (or genes), named PRRs, which play coordinately essential roles within (or dose to) the Arabidopsis circadian clock that is important for the control of the flowering time in plants. We also identified a receptor of plant peptide hormone, pktosulfokine, discovered by us.○Study on molecular mechanism of plant response to physical environments.We found characteristic properties of five cation/H+ exchangers of rice. Ktr/HKTtype transporters were also found to be essential for the adaptation of plants and bacteria to salinity stress and high osmolality We also revealed that nitrate transporter genes are activated by multiple mechanisms involving nitrate and/or nitrite, and also that glutamine was shown to regulate nitrate transport activity at both the transcriptional and post-translational levels. For understanding of signal transduction of responses to hyperosmotic stress, we have identified an SnRK2 interacting protein that would function as a scaffold for signaling components.