Analysis of Brassinosteroid Biosynthesis in Arabidopsis thaliana

拟南芥油菜素类固醇生物合成分析

• 批准号: 09640784
• 负责人: KOBAYASHI Masatomo
• 金额: $ 1.73万
• 依托单位: The Institute of Physical and Chemical Research
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640784/
• 关键词: brassinosteroid; dwarf mutant; arabidopsis; T-DNA tagging line; metabolism; ミュータント; 生合成; 生合成ミュータント

Brassinosteroid has been recognized as a plant hormone that regulates growth of plants. Dwarf mutants of Arabidopsis thaliana that are deficient in endogenous brassinosteroid levels have been used for studies on the biosynthesis of brassinosteroid. In this study, following subjects have been examined to clarify the regulation of the biosynthesis of brassinosteroid in Arabidopsis.1)Establishment of experimental conditions for metabolic studies with intact plants. We have tested several methods for the treatment of substrate brassinosteroids to the intact plants of Arabidopsis. The highest efficiency was observed in the system using a liquid culture of seedlings. Micro-injection was not effective at all, and slight metabolic activity was observed in the direct injection of castasterone into Arabidopsis stems.2)Characterization of novel dwarf mutant that has defect in brassinosteroidbiosynthesis.A dwarf mutant was found in the T-DNA insertion mutant lines, which had similar phenotype with brassinosteroid mutants. Application of brassinosteroids and analysis of endogenous brassinosteroid levels revealed that it is a novel brassinosteroid mutant that has defect in the metabolic activity of typhasterol to castasterone. Cloning of the gene that is disrupted by the insertion of T-DNA was attempted, although it has not been achieved yet. This study will be published after we get successful results in the cloning work.

油菜素类固醇已被认为是一种调节植物生长的植物激素。拟南芥的矮秆突变体是缺乏内源油菜素类固醇水平已被用于研究油菜素类固醇的生物合成。本研究主要从以下几个方面探讨了油菜籽中油菜素内酯的生物合成调控：1）建立完整植株的代谢研究条件。我们已经测试了几种方法处理底物油菜素类固醇拟南芥的完整植物。最高的效率，观察到在该系统中使用的液体培养的幼苗。结果表明，微量注射法没有明显的效果，直接注射Castasterone后，拟南芥茎中仍有轻微的代谢活性。2）油菜素内酯合成缺陷矮化突变体的鉴定在T-DNA插入突变体中发现了一个表型与油菜素内酯合成缺陷突变体相似的矮化突变体。油菜素内酯的应用和内源油菜素内酯水平的分析表明，它是一个新的油菜素内酯突变体，具有缺陷的代谢活性的typhasterol castasterone。试图克隆通过插入T-DNA而被破坏的基因，尽管尚未实现。这项研究将在克隆工作取得成功后发表。