Collaborative Research: Arabidopsis NHX-like Vacuolar Antiporters: Structure and Function

合作研究：拟南芥 NHX 样液泡逆向转运蛋白：结构和功能

• 批准号: 0343279
• 负责人: Eduardo Blumwald
• 金额: $ 49.05万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-06-01 至 2009-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0343279&HistoricalAwards=false
• 关键词: Collaborative; Research; Arabidopsis; NHX; like

Cation/proton antiporters play a major role in pH and Na ion homeostasis of cells throughout the biological kingdom, from bacteria, algae, fungi and worms to higher plants and humans. These proteins are integral membrane proteins residing in the plasma membranes and endomembranes of different cells. Although the functional analysis of amino acid residues of mammals and bacteria plasma membrane-bound sodium/proton antiporters is emerging, little is known about the specific amino acids that are involved in cation/proton exchange, pH sensing, ion specificity, etc. There is no vacuolar or lysosomal transporter (animal, yeast or plant) whose topology, structure and mode(s) of action have been characterized to date. The main purpose of this research is to address this lack of critical information. The research will use a multidisciplinary approach that will combine biochemistry, molecular biology, membrane transport, heterologous expression in yeast and plants, and crystallography. The specific goals are: (i) Determine the topology of the Arabidopsis vacuolar antiporters AtNHX1 and AtNHX5; (ii) Structure/functional analysis of AtNHX1 and AtNHX5 in order to gain insight into key amino acids and regions of the protein responsible for ion binding, ion selectivity, pH regulation and transport activity; and (iii) Determine their three-dimensional structure. Broader impacts: Plant vacuolar cation/proton antiporters have been shown to play important roles in ion homeostasis and plant development. The ectopic overexpression of AtNHX1 and AtNHX5 has been shown to confer salt tolerance in Arabidopsis and other plants. An understanding of the antiporter mode(s) of action together with the identification of factors affecting its activity will augment our capability of producing plants with enhanced salt tolerance. These plants would provide an important tool for crop production in large areas of the world affected by salinity. In addition, the nature of this project provides excellent opportunity for interdisciplinary training at all levels from high school students and teachers to post-doctoral trainees.

从细菌，藻类，真菌和蠕虫到较高的植物和人类，阳离子/质子抗抗植物在整个生物王国的细胞的pH和NA离子稳态中起着重要作用。这些蛋白是位于不同细胞的质膜和内膜内膜中的积分膜蛋白。尽管哺乳动物和细菌质膜结合的钠/质子抗植物的氨基酸残基的功能分析正在出现，但对参与阳离子/质子交换，pH传感，离子特异性等的特定氨基酸的了解鲜为人知。在阳离子/质子交换，离子特异性等方面没有真空或溶酶体或溶酶体（动物，造型）的作用和模式，并且构成了造型和模式。 这项研究的主要目的是解决这种缺乏关键信息。该研究将使用多学科方法，将生物化学，分子生物学，膜转运，酵母异源表达结合在一起，以及晶体学。具体目标是：（i）确定拟南芥液泡抗毒剂ATNHX1和ATNHX5的拓扑； （ii）ATNHX1和ATNHX5的结构/功能分析，以深入了解负责离子结合，离子选择性，pH调节和转运活性的蛋白质的关键氨基酸和区域； （iii）确定其三维结构。更广泛的影响：已显示植物液泡阳离子/质子抗植物在离子稳态和植物发育中起着重要作用。 ATNHX1和ATNHX5的异位过表达已显示可在拟南芥和其他植物中赋予盐耐受性。对动作的抗毒剂模式的理解，以及鉴定影响其活性的因素的鉴定将增强我们具有增强盐耐受性的植物的能力。这些植物将为受盐度影响的世界大区域提供重要的作物生产工具。此外，该项目的性质为从高中生和老师到博士后学员的各个级别的跨学科培训提供了绝佳的机会。