Regulation of Phosphoinositide Metabolism and Plasma Membrane Signaling

包括干旱在内的极端气候变化限制了许多作物的生长和生产力。不幸的是，通过改变基本代谢途径或减少叶片气体交换来减少植物水分损失的遗传方法往往会对最佳条件下的植物生长产生负面影响。为了有选择地增加对压力的耐受性，我们需要更好地理解感知环境刺激的机制。脂质，特别是质膜中的肌醇磷脂，细胞的最外层膜，为水势的变化提供了早期感知机制。最重要的假设是，通过改变植物用来感知水势变化的机制，人们可以选择性地改变植物对压力的反应，而不影响正常的生长。本研究将确定调节质膜肌醇磷脂代谢的特定蛋白质。该项目将使用分子，生物化学和细胞生物学相结合的方法来识别和表征调控这种质膜传感系统的基因和蛋白质。一旦确定了预测植物对渗透胁迫反应的基因，通过遗传学方法将产生具有改变的脂质代谢和改变的植物对干旱的反应的植物。该项目的重要基本成果将是：1）确定用于改善植物对环境胁迫如干旱的反应的选择性蛋白质; 2）增加对这些蛋白质在胁迫反应期间调节膜肌醇磷脂代谢的基本机制的理解; 3）产生对环境刺激具有可预测改变的反应的转基因植物; 4）支持本科生和研究生的研究和培训，以及生产转基因植物，用作本科生实验室的教材。

Extreme climate changes, including drought, limit the growth and productivity of many crop plants. Unfortunately, genetic approaches to decrease water loss in plants by altering basic metabolic pathways or decreasing gas exchange through the leaves have often negatively impacted plant growth under optimal conditions. To selectively increase tolerance to stress, we need a better understanding of the mechanisms involved in sensing environmental stimuli. Lipids, specifically inositol phospholipids in the plasma membrane i.e., outermost membrane of a cell, provide an early sensing mechanism for changes in water potential. The overarching hypothesis is that by altering the mechanisms plants use to sense changes in water potential, one can selectively alter a plant's response to stress without compromising normal growth. This research will identify the specific proteins that regulate the metabolism of plasma membrane inositol phospholipids. The project will use a combined molecular, biochemical and cell biological approach to identify and characterize the genes and proteins regulating this plasma membrane sensing system. Once genes have been identified that predict plant responses to osmotic stress a genetic approach will generate plants with altered lipid metabolism and altered plant responses to drought.Important fundamental outcomes of this project will be: 1) identification of selective proteins to target for improving plant responses to environmental stress such as drought; 2) increased understanding of the fundamental mechanisms by which these proteins function to regulate membrane inositol phospholipids metabolism during stress response; 3) production of transgenic plants with predictably altered responses to environmental stimuli; 4) support for undergraduate and graduate research and training and the production of transgenic plants to be used as teaching material for undergraduate laboratories.