Functional characterization of a putative Arabidopsis thaliana phosphatidylinositol transfer protein which increases Al tolerance in yeast

拟南芥磷脂酰肌醇转移蛋白的功能表征，该蛋白可增加酵母的铝耐受性

• 批准号: 5453352
• 负责人: Professor Dr. Gabriel Schaaf
• 金额: --
• 依托单位: Bereich Pflanzenernährung
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5453352?language=en
• 关键词: Functional; characterization; putative; Arabidopsis; thaliana

Aluminum (Al) toxicity is a major limiting factor for crop production worldwide. The proposed research builds on the discovery of an Arabidopsis cDNA, AtAlr54, which encodes a protein homologous to the yeast Sec14p phosphatidyl inositol transfer protein (PITP) and whose expression causes increased Al tolerance in yeast. Because AtAlr54 shares homology with yeast Sec14p and complements the growth defect of a yeast sec14-1ts mutant, AtAlr54 is itself likely a PITP. Subsequent genetic experiments with yeast mutants defective in the metabolism of phosphoinositides suggested that AtAlr54-mediated increased Al tolerance might act by regulating amount or distribution of phosphoinositides. The proposed research addresses the biochemical characterization of AtAlr54 as a first step towards investigating the function of PITPs in Al tolerance. This characterization will include comprehensive biochemical analyses of AtAlr54 lipid binding and transfer properties, metabolic experiments designed to measure how AtAlr54 affects phosphoinositide and soluble inositol phosphate metabolism in vivo, genetic and mutagenesis experiments to determine what lipid signaling pathways are involved in AtAlr54-mediated Al tolerance, and imaging experiments to monitor phosphoinositide distribution in response to metal stress. This research will employ yeast as a system to get a picture of how AtAlr54 functions, and will guide functional analyses in plants engineered for altered AtAlr54 expression.

铝毒是全球农作物生产的主要限制因素。拟进行的研究建立在发现拟南芥cDNA AtAlr 54的基础上，AtAlr 54编码与酵母Sec 14 p磷脂酰肌醇转移蛋白（PITP）同源的蛋白质，其表达导致酵母中Al耐受性增加。由于AtAlr 54与酵母Sec 14 p具有同源性，并补充了酵母sec 14 - 1 ts突变体的生长缺陷，因此AtAlr 54本身可能是一种PITP。随后的遗传实验与酵母突变体的磷酸肌醇代谢缺陷表明，AtAlr 54介导的铝耐受性增加可能会通过调节磷酸肌醇的量或分布。拟议的研究解决了AtAlr 54的生化特性作为第一步，调查铝耐受性的功能的PITP。该表征将包括AtAlr 54脂质结合和转移特性的全面生化分析，旨在测量AtAlr 54如何影响体内磷酸肌醇和可溶性磷酸肌醇代谢的代谢实验，确定AtAlr 54介导的铝耐受性中涉及哪些脂质信号传导途径的遗传和诱变实验，以及监测磷酸肌醇分布的成像实验。这项研究将采用酵母作为一个系统，以了解AtAlr 54的功能，并将指导植物的功能分析工程改变AtAlr 54的表达。