Enhancement mechanism of chilling torelance induced by a novel steroidal phytohormone, brassinosteroid.

新型甾体植物激素油菜素类固醇诱导的耐寒性增强机制。

• 批准号: 09460024
• 负责人: ABE Hiroshi
• 金额: $ 1.28万
• 依托单位: Tokyo University of Agriculture and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09460024/
• 关键词: Steroidal plant hormone; Brassinosteroid; Brassinolide metabolism; Chilling stress tolerance; Acid brassinosteroid; 植物ホルモン; ブラシノライド; 低温ストレス

This is study on a mechanism of chilling tolerance enhancement induced by treatment with brassinolide. Rice seedling was higher than that of cucumber seedling in sensitivity when searching a signal transduction of the chilling stress. Effect of brassinolide was appeared remarkably in the root growth under the chilling stress condition. The timing of brassinolide treatment was more effective with pre-treatment before the seedling was put in the chilling stress condition than with simultanious treatment or post- treatment after in the stress condition. Oxidation activity was strongly increased in the brassinolide-treated root tissue. This suggests that brassinolide promotes the growth of root and enhances nutrient absorption from root, so that a signal transduction system for the chilling stress response is activated. Humidity, especialy to keep it lower, was important to enhance the effect of brassinolide. Durability of brassinolide activity was short and it shows that brassinolide treated exogenously was rapidly metabolited in the seedling. In cucumber seedling brassinolide was easily epimerized to an isomer possessing the same molecular as brassinolide and then it was converted to conjugate coupled with a sugar and/or a fatty acid. The structures of the conjugate and its aglycone were undertaken to physicochemical analyses after chemical derivatization and also their spectral data were compared with several presumable compounds synthesized chemically and metabolites induced by cucumber cell suspension culture. In spite of them analyses determination of the structures have been not elicidated. On the other hand, several compounds of acid brassinolide with almost same activity as auxin in the lamina joint test. Chilling tolerance activity and its durability must be confirmed.

本文研究了油菜素钠处理提高植物耐冷性的机理。在寻找低温胁迫信号转导途径时，水稻幼苗的敏感性高于黄瓜幼苗。低温胁迫条件下，油菜幼苗根系生长表现出明显的油菜素效应。在低温胁迫前进行预处理比低温胁迫后或低温胁迫后进行后处理更能有效地提高油菜素酶活性。油菜素内酯处理的根组织中的氧化活性强烈增加。这表明油菜素能促进根系生长，增强根系对养分的吸收，从而激活了低温胁迫反应的信号转导系统。湿度，特别是保持较低的湿度，对提高油菜籽的保绿效果很重要。油菜素内酯活性持续时间短，表明外源处理的油菜素内酯在幼苗中代谢迅速。在黄瓜幼苗中，芸苔素很容易差向异构化为与芸苔素具有相同分子的异构体，然后转化为与糖和/或脂肪酸偶联的缀合物。经化学衍生化后，对偶联物及其苷元的结构进行了理化分析，并与化学合成的几种可能化合物及黄瓜细胞悬浮培养诱导的代谢产物进行了光谱比较。尽管有这些分析，结构的确定还没有得到启发。另一方面，在叶片联合试验中，发现了几种与生长素活性相近的酸性芸苔素化合物。必须确认耐寒活性及其耐久性。

项目成果

R.Hatta, T.Miki, T.Ando and H.Abe: "Synthesis of 3-epicastasterone and structure elucidation by ^1H-NMR analysis" Biosci.Biotech.Biochem.(submitted). (1999)

R.Hatta、T.Miki、T.Ando 和 H.Abe：“3-表卡斯特酮的合成和通过 ^1H-NMR 分析进行结构阐明”Biosci.Biotech.Biochem.（已提交）。

T.Miki, M.Natsume and H.Abe: "Tautomeric conversion in the A/B ring fusion of castasterone" J.Pesticide Science. (submitted). (1999)

T.Miki、M.Natsume 和 H.Abe：“卡斯特酮 A/B 环融合中的互变异构转化”J.Pesticide Science。

N.N-Koseki, M.Sugiyama and H.Abe: "Metabolism of brassinolide in cucumber seedling and cultured cells" J.Plant Physiology. (submitted). (1999)

N.N-Koseki、M.Sugiyama 和 H.Abe：“黄瓜幼苗和培养细胞中油菜素内酯的代谢”J.Plant Physiology。

R.Hatta, T.Miki, T.Ando and H.Abe: "Synthesis of 3-epicastasterone and structure elucidation by ^1H-NMR , analysis" Biosci.Biotech.Biochem.(submitted). (1999)

R.Hatta、T.Miki、T.Ando 和 H.Abe：“3-表卡斯特酮的合成和通过 ^1H-NMR 进行结构阐明、分析”Biosci.Biotech.Biochem.（已提交）。