Arabidopsis 2010: Functions of the XTH Proteins of Arabidopsis

本研究是对模式植物拟南芥木葡聚糖内切葡糖苷酶/水解酶(Xth)基因的功能分析。XTHs能够修饰植物细胞壁的主要成分木葡聚糖，但这些酶的生理功能尚不清楚。细胞壁是植物细胞的基本结构，控制细胞的形状、大小和完整性，并在信号转导中发挥作用。修饰壁多糖的酶可能在植物的形态发生和生理中起关键作用。我们将采取广泛的综合方法来阐明XTHs的生化和生理功能。将寻求第Xth基因内的突变和突变表型，除了壁属性和适应不同环境的能力外，还表现在生长、发育和整体适应能力方面。XTH的表达模式将被确定。报告基因分析将揭示表达的组织、器官和发育特异性。将用异源系统生产酶，并将在不同的同工酶之间比较它们的性质，如底物偏好和反应条件。这些实验的完成将改进关于植物细胞壁是如何形成、维护和修改的概念，以及这些特性如何影响植物的整体健康、发育和生理。研究结果将通过(http://www.bioc.rice.edu/~braam/projects/xth.html)，研究出版物和公开演示网站传播。突变的种子库将存放在俄亥俄州立大学的ABRC中，以便分发给社区。此外，这项研究将通过对博士后、研究生和本科生的持续支持和实验室培训来加强研究和培训的基础设施。该协会致力于提高妇女和少数群体在科学界的代表性。本科生还将通过莱斯大学的实验室课程参与科学发现过程。基于PCR的筛选方法和报告基因表达分析已经得到优化，以便本科生可以通过实验室课程为研究做出贡献。受此资助的学生将被鼓励参加会议和教学机会。

This research is a functional analysis of the xyloglucan endotransglucosylase/hydrolase (XTH) genes of the model plant Arabidopsis. XTHs are capable of modifying xyloglucan, a major component of the plant cell wall, and yet the physiological functions of these enzymes are not understood. The wall is a fundamental structure of plant cells that controls cellular shape, size and integrity, and plays a role in signal transduction. Enzymes that modify wall polysaccharides likely play critical roles in plant morphogenesis and physiology.A broad-based integrative approach will be taken to elucidate the biochemical and physiological functions of XTHs. Mutations within XTH genes will be sought and mutant phenotypes characterized with respect to growth, development and overall fitness, in addition to wall properties and ability to adapt to diverse environments. Expression patterns of XTHs will be determined. Reporter gene analyses will shed light on tissue, organ, and developmental specificity of expression. Enzymes will be produced with heterologous systems and their properties, such as substrate preferences and reaction conditions, will be compared among the different isozymes. Completion of these experiments will improve concepts of how plant cell walls are formed, maintained and modified, and how these properties impact the overall fitness, development and physiology of plants.Research results will be disseminated through a website (http://www.bioc.rice.edu/~braam/projects/xth.html), research publications, and public presentations. Mutant seed stocks will be deposited in the ABRC at Ohio State University for distribution to the community. In addition, this research will enhance the infrastructure of research and training through the continued support and laboratory training of postdoctoral, graduate and undergraduate students. The PI is committed to increasing the representation of women and underrepresented minorities in science. Undergraduates will also participate in the scientific discovery process through Rice University laboratory courses. PCR-based screening methods and reporter gene expression analyses have been optimized such that undergraduates can contribute to research through lab courses. The students supported by this grant will be encouraged to participate in conferences and teaching opportunities.