Roles of subcellular amino acid transporters in source and sink function

亚细胞氨基酸转运蛋白在源库功能中的作用

• 批准号: 1932661
• 负责人: Mechthild Tegeder
• 金额: $ 66.48万
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1932661&HistoricalAwards=false
• 关键词: Roles; subcellular; amino; acid; transporters

Plants require large amounts of nitrogen for growth and development. The nitrogen is generally taken up from the soil and then used to produce amino acids. These amino acids play highly diverse and essential roles in plants. They are the basic units of proteins and enzymes, and thereby fundamental to cellular structure and metabolism. Moreover, they are crucial for the synthesis of a large variety of compounds, such as chlorophyll, vitamins and other products needed for plant function as well as for human nutrition. In addition, amino acids serve as signaling molecules triggering physiological processes including plant responses to environmental stresses, and they present the main long-distance nitrogen forms transported to seeds for growth. This project intends to provide pioneering insights on the mechanisms of amino acid partitioning within the cell and their importance for leaf and seed development, and plant survival. It is expected to discover strategies on how amino acid movement can be manipulated to alter nitrogen supply into specific metabolic and transport pathways, with consequences for plant growth, productivity and responses to environmental stresses. The activities will further promote student teaching and training, and foster effective integration of plant biology education and research.A fundamental process in plants is the selective partitioning of amino acids among different organelles, cells, tissues and organs. Various transport mechanisms must exist within the cell to accommodate their directional transport, and these mechanisms must be coordinated and regulated at different levels to achieve normal physiological functions. In Arabidopsis, more than 100 putative amino acid transporters have been identified but physiological functions in nitrogen transport have only been demonstrated for relatively few transporters, and these are mainly plasma membrane-localized. This project intends to identify novel subcellular amino acid transporters and resolve their substrate specificity and mechanisms of transport. Plants, in which the transporters are knocked-out, knocked-down or overexpressed will be analyzed using molecular, cell-biological and biochemical approaches to unravel the physiological functions of the membrane proteins and their importance for plant growth and development. Finally, amino acids have been shown to play important roles in plant performance under environmental stress conditions. The transporter mutants or overexpressors will be exposed to abiotic stresses and their responses will be examined. Together, this project will help to resolve the function of intracellular membrane transporters and their role in nitrogen partitioning between cellular compartments to promote source leaf function, and in long distance amino acid transport in support of seed development. Evidence will be found on how specific amino acid transporters interconnect nitrogen and carbon metabolism, and other biochemical pathways, and if and how they influence plant responses to abiotic stress.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

植物需要大量的氮才能生长和发育。通常从土壤中取氮，然后用于产生氨基酸。这些氨基酸在植物中起着高度多样化和重要作用。它们是蛋白质和酶的基本单位，因此是细胞结构和代谢的基础。此外，它们对于合成多种化合物的合成至关重要，例如叶绿素，维生素和其他用于植物功能以及人类营养所需的产品。此外，氨基酸是触发生理过程的信号分子，包括植物对环境应激的反应，它们呈现出主要的长距离氮形式，该氮形式运送到种子上以供生长。该项目旨在提供有关细胞内氨基酸分配机制的开创性见解及其对叶片和种子发育以及植物生存的重要性。预计将发现如何操纵氨基酸运动以将氮的供应改变为特定的代谢和运输途径，这对植物生长，生产力和对环境压力的反应产生了影响。这些活动将进一步促进学生的教学和培训，并促进植物生物学教育和研究的有效整合。植物的基本过程是对不同细胞器，细胞，组织和器官之间氨基酸的选择性分配。细胞内必须存在各种运输机制，以适应其方向运输，并且这些机制必须在不同水平上进行协调并调节以达到正常的生理功能。在拟南芥中，已经确定了100多个推定的氨基酸转运蛋白，但仅在相对较少的转运蛋白中证明了氮转运中的生理功能，这些功能主要是质膜 - 位置。该项目旨在鉴定新型的亚细胞氨基酸转运蛋白并解决其底物的特异性和运输机制。将使用分子，细胞生物和生化方法分析转运蛋白被敲除，倒下或过表达的植物，以揭示膜蛋白的生理功能及其对植物生长和发育的重要性。最后，在环境应力条件下，氨基酸已被证明在植物性能中起重要作用。转运蛋白突变体或过表达者将暴露于非生物胁迫下，将检查其反应。该项目一起将有助于解决细胞内膜转运蛋白的功能及其在细胞隔室之间氮分配中的作用，以促进源叶的功能，并在长距离氨基酸转运中支持种子发育。将发现有关特定氨基酸转运蛋白如何相互连接的氮和碳代谢以及其他生化途径的证据，以及它们是否以及它们如何影响植物对植物对非生物压力的反应。该奖项反映了NSF的法定任务，并通过使用该基金会的智力优点和广泛的影响来评估NSF的法定任务，并被视为值得通过评估的支持。

项目成果

A Research Road Map for Responsible Use of Agricultural Nitrogen

• DOI: 10.3389/fsufs.2021.660155
• 发表时间: 2021-05
• 作者: M. Udvardi;F. Below;M. Castellano;Alison J Eagle;K. Giller;J. Ladha;Xuejun Liu;T. Maaz;Bárbara Nova-Franco;N. Raghuram;G. Robertson;Sonali Roy;M. Saha;S. Schmidt;M. Tegeder;L. York;J. W. Peters