Lipid Metabolism and Photosynthesis in Fatty Acid Mutants ofArabidopsis

拟南芥脂肪酸突变体的脂质代谢和光合作用

• 批准号: 9407902
• 负责人: John Browse
• 金额: $ 51.82万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-07-15 至 2000-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9407902&HistoricalAwards=false
• 关键词: Lipid; Metabolism; Photosynthesis; Fatty; Acid

9407902 Browse The acyl lipids of chloroplasts contain characteristically high proportions of trienoic fatty acids. However, the free radical by- products of the photosynthetic light reactions can lead to oxidation of polyunsaturated fatty acids. Because this might be expected to mediate against a high degree of unsaturation, it has been inferred that trienoic fatty acids must have some crucial role in supporting photosynthesis. Other unusual lipid features typical of chloroplasts have provoked similar speculation about membrane structure and function. To approach this research area in a novel way, a series of Arabidopsis mutants with specific alterations in leaf fatty acid composition have been isolated. In the last six years, these have provided a means to study both the synthesis of chloroplast glycerolipids and the physiological significance of membrane lipid composition. This proposal describes experiments in which the mutants and the desaturase genes will be used together to produce plant lines with progressively more severe alterations in thylakoid lipid composition. These lines will be studied under a range of environmental conditions using non-invasive chlorophyll fluorescence techniques, assays of photosynthetic electron transport, and measurements of membrane fluidity. These experiments will provide data on the minimum levels of particular fatty acid types that are needed to sustain chloroplast function. They should also reveal which photosynthetic processes are most susceptible to membrane disruption. The improved understanding of membrane lipid metabolism and photosynthesis that will result from this work are important prerequisites to modifying these processes for increased plant productivity. ***

9407902 浏览 叶绿体的酰基脂质含有高比例的三烯脂肪酸。 然而，光合作用光反应的自由基副产物可导致多不饱和脂肪酸的氧化。 因为这可能会介导高度不饱和度，所以推测三烯脂肪酸在支持光合作用中一定具有某些关键作用。 叶绿体典型的其他不寻常的脂质特征也引发了关于膜结构和功能的类似推测。 为了以一种新颖的方式进入这一研究领域，我们分离出了一系列叶脂肪酸组成发生特定改变的拟南芥突变体。 在过去的六年中，这些为研究叶绿体甘油脂的合成和膜脂组成的生理意义提供了一种手段。 该提案描述了将突变体和去饱和酶基因一起使用来产生类囊体脂质组成逐渐发生更严重改变的植物系的实验。 这些品系将在一系列环境条件下使用非侵入性叶绿素荧光技术、光合电子传输测定和膜流动性测量进行研究。 这些实验将提供维持叶绿体功能所需的特定脂肪酸类型的最低水平的数据。 他们还应该揭示哪些光合作用过程最容易受到膜破坏的影响。 这项工作将提高对膜脂代谢和光合作用的理解，这是修改这些过程以提高植物生产力的重要先决条件。 ***