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做出反应的能力。鞘脂在植物细胞的基本过程中也起着重要的调节作用，包括对病原体的反应引发细胞死亡。鞘脂以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作用尚不清楚。这个问题将在这个项目中通过产生模式植物拟南芥和番茄的突变体来解决，这些突变体在鞘脂结构上有明确的改变。这些突变体将通过先进的分析方法来确定对全球鞘脂代谢的影响。研究还将对拟南芥和番茄突变体进行研究，以研究鞘脂组成的改变如何影响生长，以应对环境压力，包括干旱和高土壤盐度。除了产生关于鞘脂代谢和植物功能的基本新知识外，研究结果还将为通过育种和生物技术提高作物的性能和生产力提供信息。更广泛的影响：该项目将为高中生和大学生提供教育机会。PI和共同PI将参与“植物研究与教育伙伴关系”（Partnership in Research and Education in Plants）项目，该项目允许高中生利用模式植物拟南芥（Arabidopsis）的突变体设计实验，从而让他们参与科学过程。PI和联合PI将在密苏里州圣路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。学生们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应激反应的假设。学生将通过在线实验笔记本与PI和co-PI保持互动。该项目还旨在通过内布拉斯加大学林肯分校本科生创造性活动和研究经验（UCARE）计划为本科生提供研究机会，这是一个为期两年的计划，允许学生进行文献研究并开发独立的研究项目。通过参与UCARE， PI将招募并指导一名本科生，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.