Regulation of plastid metabolism in higher plants

该建议的目的是提高我们对高等植物质体代谢途径调控的基本理解。特别是，该研究计划将调查管理生育酚生物合成的调节机制在油料种子质体中，发育细胞器内的组织途径，以及它与其他主要代谢途径的关系。生育酚和生育三烯酚是一组重要的脂溶性抗氧化剂，仅在光合组织中合成，具有许多有益的特性，既对人类健康有益（例如维生素E活性），又在食品工业中作为稳定剂和防腐剂，因此是主要油籽作物如大豆（Glycine max L.）的有价值的副产物。我们计划采取多学科的方法来了解生育酚和生育三烯酚生物合成的调节和组织在叶叶绿体的拟南芥（一种遗传上顺从的植物，也是一种油料种子）和光合异养质体的发展中的油料种子，如大豆。具体而言，这些技术将用于检查质体内途径的组分（内膜和亚质体区室，如质体微囊），并鉴定其他尚未发现的与生育酚生物合成途径组分相互作用的蛋白质，例如调节因子或信号转导级联和质体内运输系统的元件。这项研究将为高等植物质体中重要代谢途径的控制和调节机制提供重要见解，并有助于工程作物提高营养价值和增强高价值生物产品。

The objective of this proposal is to improve our fundamental understanding of the regulation of plastid metabolic pathways in higher plants. In particular, the research program will investigate the regulatory mechanisms governing tocopherol biosynthesis in oilseed plastids, the organization of the pathway within developing organelles, and its relationship to other major metabolic pathways. Tocopherols and tocotrienols are an important group of lipid-soluble antioxidants synthesized exclusively in photosynthetic tissues, with many beneficial properties, both with respect to human health (e.g. vitamin E activity), and within the food industry as stabilizers and preservatives, and are therefore a valuable by-product of major oilseed crops such as soybean (Glycine max L.). We plan to take multi-disciplinary approaches to understanding the regulation and organization of tocopherol and tocotrienol biosynthesis both in leaf chloroplasts of Arabidopsis (a genetically amenable plant and also an oilseed) and photoheterotrophic plastids of developing oilseeds such as soybean. Specifically, these techniques will be employed to examine the components of the pathway within plastids (inner membranes, and sub-plastidial compartments such as the plastoglobules), and identify other, as yet undiscovered, proteins interacting with components of the tocopherol biosynthetic pathway, e.g. regulatory factors or elements of signal transduction cascades and intra-plastidial trafficking systems. This research will provide important insights into the mechanisms governing the control and regulation of important metabolic pathways in the plastids of higher plants, and contribute to engineering crops with improved nutritional value and enhanced high-value bioproducts.