Probing the Metabolic and Physiological Significance of Sphingolipid Long-Chain Base Desaturation in Plants

科学价值：鞘脂是植物细胞外膜的重要组成部分，它们有助于植物对极端环境的反应能力。鞘脂还在调节植物细胞的基本过程中发挥重要作用，包括响应病原体而启动细胞死亡。鞘脂作为不同化学结构的复杂混合物存在于植物中。不同鞘脂对植物生长和生理的具体贡献还不清楚。这个问题将在本项目中解决的模式植物拟南芥和番茄的突变体的产生与定义的鞘脂结构的改变。这些突变体将通过先进的分析方法进行表征，以确定对全球鞘脂代谢的影响。还将对拟南芥和番茄突变体进行研究，以检查鞘脂组成的改变如何影响生长以应对环境胁迫，包括干旱和高土壤盐分。除了产生关于植物中鞘脂代谢和功能的基础新知识外，研究结果还将提供信息，通过育种和生物技术提高作物的性能和生产力。更广泛的影响：该项目将为高中和本科生提供教育机会和宣传。PI和co-PI将参与植物研究和教育合作伙伴关系，该计划通过允许高中生使用模式植物拟南芥的突变体设计实验，使他们参与科学过程。 PI和co-PI将在密苏里州圣刘易斯地区的一所高中与参与的学生会面，并描述细胞膜以及鞘脂在人类健康和植物生长中的重要功能。 学生将获得拟南芥突变体的种子，他们将使用这些种子进行实验，以测试有关生长和环境胁迫反应的假设。学生将通过在线实验室笔记本与PI和co-PI保持互动。该项目还旨在通过内布拉斯加-林肯大学本科生创意活动和研究经验（UCARE）计划，一个为期两年的计划，让学生进行文献研究和开发一个独立的研究项目的大学提供研究机会。通过参与UCARE，PI将招募和指导一名本科生，研究鞘脂成分改变对番茄和拟南芥生长和生理的影响。

Scientific Merit:Sphingolipids are essential components of the outer membrane of plant cells where they contribute to the ability of plants to respond to environmental extremes. Sphingolipids also play important roles in the regulation of basic processes in plant cells, including the initiation of cell death in response to pathogens. Sphingolipids occur in plants as complex mixtures of different chemical structures. The specific contributions of different sphingolipids to the growth and physiology of plants is not well understood. This question will be addressed in this project by the generation of mutants of the model plants Arabidopsis and tomato with defined alterations in sphingolipid structures. These mutants will be characterized by advanced analytical methods to determine the impact on global sphingolipid metabolism. Studies will also be conducted with Arabidopsis and tomato mutants to examine how altered sphingolipid composition affects growth in response to environmental stresses, including drought and high soil salinity. In addition to generating fundamental new knowledge on sphingolipid metabolism and function in plants, the results will provide information that could lead to improving the performance and productivity of crop plants through breeding and biotechnology.Broader Impacts:The project will offer educational opportunities and outreach to high school and undergraduate students. The PI and co-PI will participate in the Partnership in Research and Education in Plants, a program that engages high school students in the scientific process by allowing them to devise experiments using mutants of the model plant Arabidopsis. The PI and co-PI will meet with participating students at a Saint Louis, Missouri-area high school and describe the important functions of cellular membranes as well as sphingolipids in human health and plant growth. The students will be provided with seeds for Arabidopsis mutants that they will use for experiments to test hypotheses regarding growth and environmental stress responses. The students will maintain interactions with the PI and co-PI through an online laboratory notebook. The project is also designed to provide research opportunities to undergraduates through the University of Nebraska-Lincoln Undergraduate Creative Activities and Research Experiences (UCARE) program, a two-year program that allows students to conduct literature research and develop an independent research project. Through participation in UCARE, the PI will recruit and mentor an undergraduate student examining the effects of altered sphingolipid composition on growth and physiology of tomato and Arabidopsis.