Characterization of GC ABA Receptor Coupled to KAT1 Expressed in Xenopus Oocytes

爪蟾卵母细胞中表达的 GC ABA 受体与 KAT1 偶联的表征

• 批准号: 0091295
• 负责人: Fedora Sutton
• 金额: $ 30.84万
• 依托单位: South Dakota State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0091295&HistoricalAwards=false
• 关键词: Characterization; GC; ABA; Receptor; Coupled

Urbanization, flooding, drought and salinization of soil are diminishing landmass needed to supply food for an expanding world population. Together with contined global efforts to safeguard agricultural land for future food production, it is important to understand how plants function so that they can be bred or modified to survive the harsher environments. A critical aspect of plant function is ion, water and nutrient movement across membranes. This research focuses on receptors, ion channels, transporters and the mechanism(s) by which they are regulated. The Xenopus oocyte system is used for functional expression of plant mRNA. The source of mRNA is guard cells because they play a critical role in controlling water loss and gaseous exchange. V. faba is the experimental plant choice because research on ion channel and signal transduction of V. faba guard cells is extensive. The two electrode voltage clamp (TEVC) technique is used for the assay. Preliminary results have shown that oocytes injected with V. faba guard cell mRNA (GC mRNA) express a GC specific ABA receptor that inhibits activity of the inward rectifying K + channel, KAT1. This research will test the hypothesis that: ABA modulation of KAT1 is via an extra-cellular facing plasma membrane receptor. A cDNA clone for this receptor will be isolated. The identification of a GC-specific ABA receptor will lead to the identification of one sub-type of the ABA receptor. It may be possible by conservation of homology among receptors to isolate the other subtypes. Sequencing information from the isolated clones will allow use of bioinformatics to identify other proteins in the databases with related functions. The long-term goal of this research is to understand how ABA controls ion uptake during the exchange of water and carbon dioxide in photosynthesis. The research outlined will permit student training in molecular biology, electrophysiology and bioinformatics. The identified plant genes will provide targets for genetic modification and herbicide or chemical manipulation of plant function, thus allowing plants to survive in inhospitable environmental conditions.

城市化、洪水、干旱和土壤盐碱化正在减少为不断增加的世界人口提供粮食所需的陆地面积。随着全球不断努力保护农业用地以供未来粮食生产，了解植物如何发挥作用，以便它们能够繁殖或改造以在更恶劣的环境中生存，这一点非常重要。植物功能的一个关键方面是离子、水和营养物质的跨膜运动。这项研究的重点是受体，离子通道，转运蛋白及其调节机制。非洲爪蟾卵母细胞系统用于植物mRNA的功能性表达。mRNA的来源是保卫细胞，因为它们在控制水分流失和气体交换中起着关键作用。由于蚕豆保卫细胞离子通道和信号转导的研究较为广泛，因此选择蚕豆作为实验植物。双电极电压钳（TEVC）技术用于测定。初步结果表明，注射蚕豆保卫细胞mRNA（GC mRNA）的卵母细胞表达GC特异性ABA受体，该受体抑制内向整流K+通道KAT 1的活性。本研究将验证以下假说：ABA对KAT 1的调节是通过一个面向细胞外的质膜受体实现的。将分离该受体的cDNA克隆。GC特异性ABA受体的鉴定将导致ABA受体的一种亚型的鉴定。通过受体间同源性的保守性，分离其他亚型是可能的。来自分离的克隆的测序信息将允许使用生物信息学来鉴定数据库中具有相关功能的其他蛋白质。这项研究的长期目标是了解ABA如何控制光合作用中水和二氧化碳交换过程中的离子吸收。概述的研究将允许学生在分子生物学，电生理学和生物信息学方面的培训。已鉴定的植物基因将为基因改造和除草剂或化学操纵植物功能提供目标，从而使植物能够在恶劣的环境条件下生存。