Essential Nature of Fatty Acid Elongation in Plant Development

含有20个或更多碳单元的超长链脂肪酸（VLCFAs）被纳入多种具有重要生理意义的植物化学物质中，包括角质层蜡质、角质层、亚木质素、鞘脂以及一些磷脂和种子油。编码几种参与VLCFAs产生的酶的基因已经被分离出来。基于阻断其中一种酶产生的玉米突变体是胚胎致死的发现，VLCFAs在玉米胚胎发生过程中一定是必不可少的。因此，阻断必需VLCFAs积累的突变体为确定vlcffa衍生的植物化学物质在植物发育中的重要作用提供了理想的实验系统。拟议的项目将通过确定区分突变胚胎与正常胚胎发育的形态学差异来定义VLCFAs的基本发育作用。通过比较正常胚胎和突变胚胎中vlcfa衍生化合物的积累，还将确定哪些vlcfa衍生化合物在胚胎发育过程中是必不可少的。最后，将分离出在VLCFAs产生过程中克服与基因块相关的胚胎致死性的突变体。从长远来看，这些突变体可以用来剖析利用VLCFAs的各种生化途径网络。拟议的研究通过继续利用整合遗传和生化方法的长期研究合作中固有的协同作用，满足了理解生物化学与发育之间复杂相互作用的挑战。该项目将结合假设驱动和全基因组分析，并应用尖端技术来解决植物生物学中已被证明难以用单一学科方法解决的重大问题，因此将为不同群体的早期职业科学家提供优秀的跨学科培训经验。

Very long chain fatty acids (VLCFAs), those that contain 20 or more carbon units, are incorporated into a wide variety of physiologically significant phytochemicals, including cuticular waxes, cutin, suberin, sphingolipids, and some phospholipids and seed oils. Genes that encode several of the enzymes involved in the production of VLCFAs have been isolated. Based on the finding that maize mutants that block the production of one of these enzymes are embryo lethal, VLCFAs must be essential during maize embryogenesis. Mutants that block the accumulation of essential VLCFAs therefore provide an ideal experimental system to determine the essential role of VLCFA-derived phytochemicals in plant development.The proposed project will define the essential developmental role(s) of VLCFAs, by determining the morphological differences that distinguish the development of mutant embryos from normal embryos. It will also establish which VLCFA-derived compound(s) are essential during embryo development, by comparing the accumulation of VLCFA-derived compounds in normal and mutant embryos. Finally, mutants that overcome the embryo lethality associated with genetic blocks in the production of VLCFAs will be isolated. In the long term, these mutants can be used to dissect the diverse network of biochemical pathways that utilize VLCFAs.The proposed studies meet the challenge of understanding the complex interplay between biochemistry and development by continuing to exploit the synergy inherent in a long-term research collaboration that integrates genetic and biochemical approaches. This project will provide excellent cross-disciplinary training experiences to a diverse group of early-career scientists because it will use a combination of hypothesis-driven and genome-wide analyses, and apply cutting-edge technologies to address significant questions in plant biology that have proven recalcitrant to a mono-disciplinary approach.