The role of the FEI Pathway in Regulating Cell Wall Synthesis

非技术总结：植物细胞壁是多种多样且高度动态的结构，对发育和环境信号作出反应。它们是建筑材料、纸张、生物燃料、棉花和许多其他有用产品的主要来源，对植物的生长发育也起着至关重要的作用。尽管从实践和基础的角度来看它们都很重要，但调控植物细胞壁功能和组装的信号通路才刚刚开始被理解。该项目旨在获得关于植物如何调节其细胞壁合成的基本知识，这将最终有助于改善来自它们的各种产品，并将为植物生长和发育的基本方面提供见解。除了为本科生和研究生提供跨学科的培训机会外，该项目还将与旨在增加少数民族在科学领域的代表性的项目合作，并与一些旨在增加公众对植物科学理解的推广项目合作。项目技术描述：先前的研究发现了一对跨膜蛋白激酶，称为FEI1和FEI2，它们在调节纤维素的生物合成中起作用，纤维素是植物细胞壁的关键成分，是主要的承重元素。这些激酶定义了一种新的信号通路，其中包括1-氨基环丙烷-1-羧酸（ACC）的非规范作用，这种分子以前被认为仅作为植物激素乙烯生物合成的前体。我们将进行一系列的实验来进一步表征FEI信号通路及其在调节细胞壁功能中的作用。FEI途径调节纤维素生物合成的机制将被探索（目的1）。ACC和其他潜在的ACC衍生物在调节壁合成中的信号作用将被研究（目的2）。参与FEI通路的其他成分将被识别和表征，包括SHOU4，一种似乎在FEI通路中起作用的蛋白质，可能与细胞骨架有关（目的3）。这些研究将回答有关这一途径如何调节纤维素的产生以及它如何与其他元素相互作用以调节细胞壁合成的基本问题。此外，fei属于一类被称为受体样激酶的激酶，这是植物中最大的基因家族之一；只有少数RLKs的功能是已知的，因此这些发现将揭示鲜为人知的一类植物信号元件。最后，这些研究应该有助于阐明ACC在植物信号传导中的作用，并可能揭示一种新的信号化合物在植物中的重要作用。

Non-technical summary:Plant cell walls are diverse and highly dynamic structures that respond to developmental and environmental cues. They are a primary source of building materials, paper, biofuels, cotton, and many other useful products and also plays a crucial role in the growth and development of plants. Despite their importance both from a practical and fundamental point of view, the signaling pathways regulating the function and assembly of plant cell walls are just beginning to be understood. This project seeks to gain fundamental knowledge regarding how plants regulate the synthesis of their cell walls, which should ultimately help improve the diverse products derived from them and will provide insight into basic aspects of plant growth and development. In addition to providing interdisciplinary training opportunities for undergraduate and graduate students, this project will work with programs designed to increase the representation of minorities in the sciences and with several outreach programs designed to increase the public understanding of plant science. Technical Description of the Project:Previous studies identified a pair of transmembrane protein kinases, called FEI1 and FEI2, that play a role in regulating the biosynthesis of cellulose, which is a critical component of the plant cell wall and acts as the primary load-bearing element. These kinases define a novel signaling pathway that includes a non-canonical role for 1-aminocyclopropane-1-carboxylic acid (ACC), a molecule previously thought to act only as a precursor in the biosynthesis of the phytohormone ethylene. A series of experiments to further characterize the FEI signaling pathway and its role in regulating cell wall function will be pursued. The mechanism by which the FEI pathway regulates cellulose biosynthesis will be explored (Aim 1). The signaling role of ACC and other potential ACC-derivatives in regulating wall synthesis will be examined (Aim 2). Other components involved in this FEI pathway will be identified and characterized, including SHOU4, a protein that appears to act in the FEI pathway and which is likely associated with the cytoskeleton (Aim 3). These studies will answer fundamental questions regarding how this pathway regulates the production of cellulose and how it interacts with other elements to regulate cell wall synthesis. Further, the FEIs are belong to a group of kinases call the receptor-like kinase, which are one of the largest families of genes in plants; the function of only a handful of RLKs are known, and thus these findings will shed light on a poorly understood class of plant signaling elements. Finally, these studies should help elucidate a role for ACC in plant signaling and may uncover important roles for a novel signaling compound in plants.