Molecular targets and actions of ethanolamide-conjugated oxylipins in Arabidopsis thaliana

植物利用小分子作为信号来同步它们的生长、发育和对环境的反应。该提案旨在了解幼苗如何使用化学信号来调节其生长以应对不利的环境条件，这种反应使它们能够在最脆弱的时候承受环境压力。具体的研究目标包括识别信号感知机制，感知后幼苗中信号的代谢命运，以及发现幼苗胁迫期间激活的信号网络。这项研究的更广泛应用包括设计新的作物育种目标以改善田间出苗的潜力。此外，拟议的研究活动通过北德克萨斯大学新设计的研究课程与本科生培训机会相结合，该大学是一所为少数民族服务的大型公立大学。N-酰基乙醇胺（NAE）是乙醇酰胺缀合的脂肪酸衍生物，其在动物系统中包括“内源性大麻素信号通路”的广泛公认的生物活性内源性代谢物。该途径调节哺乳动物的一系列生理和行为过程，但尽管有记录表明NAE在植物系统中发生，但其生理作用仍不完全清楚。最近的证据表明，多不饱和NAEs的氧脂肽衍生物在动物和植物系统中具有强大的生物活性，并且在植物中这可能是NAEs的主要作用途径之一。本研究的目的是通过以下三个具体目标来扩展对这组生物活性脂质及其作为模式植物拟南芥幼苗生长的负调节剂的作用的理解：1）用生物素化探针鉴定NAE氧脂素靶蛋白; 2）确定NAE氧脂素是否是脂肪酸酰胺水解酶（FAAH）的底物; 3）阐明NAE氧脂素与阿坝和G蛋白信号在幼苗根和芽中的空间相互作用。这项研究的结果可能最终导致新的目标，为改善作物在环境胁迫下的出苗，也可能提供新的策略，减少竞争杂草出现在早季作物建立。除了潜在的更广泛的应用外，该项目还将通过北德克萨斯大学新设计的研究课程-生命科学高级研究（BIOL 3900）为本科生提供培训机会。

Plants use small molecules as signals to synchronize their growth, development and responses to their environment. This proposal seeks to understand how seedlings use chemical signals to modulate their growth in response to adverse environmental conditions, a response that allows them to endure environmental stress at a time when they are most vulnerable. Specific research aims include the identification of mechanisms for signal perception, the metabolic fate of signals in seedlings after perception, and the discovery of the signaling networks activated during seedling stress. Broader applications of this research include the potential for designing new breeding targets in crops for improved field emergence. In addition, the proposed research activities are integrated with undergraduate training opportunities through a newly-designed research course at the University of North Texas, a large minority-serving, public university. N-Acylethanolamines (NAEs) are ethanolamide-conjugated fatty acid derivatives that in animal systems include the widely-recognized bioactive endogenous metabolites of the "endocannabinoid signaling pathway". This pathway regulates an array of physiological and behavioral processes in mammals, but despite the documented occurrence of NAEs in plant systems, their physiological actions remain incompletely understood. Recent evidence indicates that oxylipin derivatives of polyunsaturated NAEs have potent biological activities in both animal and plant systems, and in plants this may be one major route of action for NAEs. This proposal aims to expand the understanding of this group of bioactive lipids and their role as negative regulators of seedling growth in the model plant, Arabidopsis thaliana, through the following three specific aims: 1) Identify NAE oxylipin target proteins with biotinylated probes; 2) Determine if NAE oxylipins are substrates for the fatty acid amide hydrolase (FAAH); 3) Delineate the spatial interaction of NAE oxylipins with ABA- and G-protein signaling in roots and shoots of seedlings. Results from this research may ultimately lead to new targets for the improvement of crop emergence under environmental stress, and may also offer new strategies for reduction of competing weed emergence in early season crop establishment. In addition to the potential broader applications, this project will offer training opportunities for undergraduate students through a newly-designed research course at the University of North Texas-- Advanced Research in Life Sciences (BIOL 3900).