Understanding plant cell wall structure

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。植物生长关键取决于糖基转移酶的作用，这些酶旨在围绕植物细胞构建细胞外细胞壁基质。然而，我们缺乏对这些酶的全面描述，以及它们如何构建如此复杂的超分子结构，这对植物生物学和工业，特别是农业，林业和可再生能源非常重要。美国能够通过植物细胞壁材料的微生物发酵生产大量乙醇形式的生物燃料;然而，这些程序的优化将需要对细胞壁组分的合成有深入的了解。阿拉伯半乳聚糖蛋白（AGPs）就是这样一种成分;它们是高度糖基化的富含羟脯氨酸的糖蛋白。AGP参与许多生理过程，包括植物体细胞胚胎发生、程序性细胞死亡、创伤反应和激素信号传导途径。鉴定AGP糖基转移酶基因将有助于作物改良和植物育种计划。然而，尚未鉴定出AGP糖基转移酶基因。本研究的目的是鉴定和分析AGP-半乳糖基转移酶（AGP-GalT）基因参与AGP O-连接糖基化的第一步的功能。该方法建立在我们开发的AGP-GalT测定的基础上，其将能够纯化和测试候选AGP GalT。该项目将导致细胞壁生物合成和生物质生长的理解，以满足木材，造纸，纺织，燃料和食品工业的需求。它还将允许设计新的基于AGP的生物产品，包括良性非抗原性药物输送产品。最后，它将在本科生，研究生和博士后水平提供宝贵的培训机会，以创造一个多样化的劳动力，将能够追求这些需求在未来的美国经济和环境的利益。调查人员坚信科学教育研究的使命，并尽一切努力将研究活动和当前的文献纳入他们在大学的教学使命。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Plant growth depends crucially on the action of glycosyltransferase enzymes designed to build an extracellular cell wall matrix around plant cells. Yet we lack a comprehensive description of these enzymes and how they construct such an intricate supramolecular structure which is important to plant biology and industry, particularly agriculture, forestry, and renewable energy. The U.S. is capable of producing substantial amounts of biofuel in the form of ethanol by microbial fermentation of plant cell wall material; however, optimization of these procedures will require a deep understanding of the synthesis of cell wall components. Arabinogalactan-proteins (AGPs) are one such component; they are highly glycosylated hydroxyproline-rich glycoproteins. AGPs are implicated in many physiological processes including plant somatic embryogenesis, programmed cell death, wound responses, and hormone signaling pathways. Identifying AGP glycosyltransferase genes will facilitate crop improvement and plant-breeding programs. However, no AGP glycosyltransferase genes have been identified. The objective of this proposal is to identify and analyze the function of AGP-galactosyltransferase (AGP-GalT) genes involved in the first steps of AGP O-linked glycosylation. The approach builds upon an AGP-GalT assay we developed, which will enable purification and testing of candidate AGP GalTs. This project will lead to an understanding of cell wall biosynthesis and biomass growth to meet needs of the wood, paper, textile, fuel, and food industries. It will also allow for designing new AGP-based bioproducts including benign non-antigenic drug delivery products. Finally, it will provide valuable training opportunities at the undergraduate, graduate, and postdoctoral levels to create a diverse work force that will be able to pursue these needs in the future for the benefit of the U.S. economy and the environment. The investigators believe strongly in the mission of research in science education and make every effort to incorporate research activities and current literature into their teaching mission at the university.