Functional Genomics of Hemicellulose Biosynthesis

植物细胞壁在植物的发育、抗病和细胞间的交流中起着至关重要的作用。对细胞壁生物合成的基本了解具有潜在的实际应用，包括开发能够更好地抵御病原体的作物植物，以及提供增强营养属性的植物或用于各种工业用途的新型聚合物产品。这个项目旨在了解半纤维素多糖是如何合成的，半纤维素多糖是植物细胞壁中发现的一种特殊类型的聚合物。细胞壁的生物合成需要数百种酶，但只有几种蛋白质和编码它们的基因被识别和表征。通过运用基因组学、蛋白质组学和生物信息学工具，主要研究人员将确定与植物细胞壁合成有关的候选基因，并评估它们的功能。这些研究将在三个植物系统中进行：发育时期的棉花纤维细胞，在这个时期产生大量的初级细胞壁成分；正在发育的莲子，其中储存了大量的木葡聚糖，这是细胞壁的主要成分；以及水稻组织正在快速生长。水稻被选为植物系统之一，因为最近水稻基因组序列的完成将有助于将与细胞壁生物合成相关的蛋白质与它们各自的基因序列进行匹配。首席研究人员希望识别与细胞壁生物合成的许多方面有关的基因，并将其结果和资源免费提供给植物生物界的研究人员。该项目将为本科生、研究生和博士后研究助理提供有价值的培训。它还将为代表性不足的学生提供暑期实验室体验。

Plant cell walls play crucial roles in the development of plants, their resistance to diseases, and communication between cells. A fundamental understanding of cell wall biosynthesis has potential practical applications, including the development of crops plants better able to fend off pathogens and of plants that provide enhanced nutritional attributes or new polymer products for various industrial uses. This project is aimed at understanding how hemicellulosic polysaccharides, a particular class of polymers found in plant cell walls, are synthesized. Cell wall biosynthesis requires hundreds of enzymes, but only a few of these proteins and the genes that encode them have been identified and characterized. Through strategies employing the tools of genomics, proteomics and bioinformatics, the principal investigators will identify candidate genes involved in the synthesis of plant cell walls and evaluate their function. The studies will be conducted in three plant systems: cotton fiber cells during a period of development in which large quantities of primary cell wall components are manufactured; developing nasturtium seeds that store large quantities of xyloglucan, a major cell wall component; and rice tissues undergoing rapid growth. Rice is chosen as one of the plant systems because the recent completion of the rice genome sequence will aid in matching the proteins linked to cell wall biosynthesis with their respective gene sequences. The principal investigators expect to identify genes involved in many aspects of cell wall biosynthesis and will make their results and resources freely available to researchers in the plant biology community. The project will provide valuable training for undergraduates, graduate students, and postdoctoral research associates. It will also provide summer laboratory experiences for underrepresented students.