Functional Genomics of Root Growth and Root Signaling under Drought

Henry T.Nguyen NguyenHenry@misSouri.edu(首席调查员流动)Julia Gross(联席首席调查员流动)Hans J.Bohnert(联席首席调查员流动)Robert E.Sharp(联席首席调查员流动)Gordon K.Springer(联席首席调查员流动)Daniel P.Schachtman(联席首席调查员流动)乔治亚·戴维斯(联席首席调查员流动)植物的根在水分和矿物质获取中发挥着至关重要的作用，这对植物的生长和发育是必不可少的。在干旱条件下，根可以适应继续生长，同时产生并向地上部分发出抑制植物生长的“预警”信号。一个致力于根遗传学和生理学的“植物根基因组学联盟”已经成立，其广泛的目标是了解植物根从土壤中获取水分和矿物质的分子机制，阐明根在适应干旱条件中所起的作用，并通过生物技术将这一知识转移到作物改良上。本课题主要研究水分亏缺下的根系生长维持和根冠信号转导机制。该研究方法涉及整个植物生理学、遗传学、基因组学和蛋白质组学等多个学科，其具体目标是确定干旱条件下控制根系生长和根冠通讯的基因和生化网络，具体目标有四个：(1)鉴定干旱胁迫下敏感和耐性玉米品系、缺乏脱落酸(ABA)的突变体和ABA积累不同的近等基因系的根伸长和非伸长区域的转录谱。(2)研究不同根区蛋白质组分的变化，特别是细胞壁蛋白质组分的变化，以确定与根系生长维持和耐缺水有关的因素。(3)研究干旱条件下根信号的产生和传递，为更好地了解干旱条件下的根-冠信号提供依据。(4)为进一步研究田间根的生长和信号传导提供遗传和基因组资源。这些知识将为通过根功能的遗传和代谢工程提高玉米的抗旱性提供新的途径。所有材料都将向公众开放。将维护一个植物根基因组网站，并将其与密苏里-哥伦比亚大学的玉米基因组数据库(MaizeDB)相结合。

Henry T. Nguyen NguyenHenry@missouri.edu (Principal Investigator current)Julia Gross (Co-Principal Investigator current)Hans J. Bohnert (Co-Principal Investigator current)Robert E. Sharp (Co-Principal Investigator current)Gordon K. Springer (Co-Principal Investigator current)Daniel P. Schachtman (Co-Principal Investigator current) Georgia Davis (Co-Principal Investigator current) The roots of plants play vital roles in water and mineral acquisition which are essential for plant growth and development. Under conditions of drought, roots can adapt to continue growth while at the same time producing and sending "early warning" signals to shoots which inhibit the plant growth above ground. A "Plant Root Genomics Consortium" has been formed and is dedicated to root genetics and physiology.The broad aim is to develop an understanding of the molecular mechanisms used by plant roots to acquire water and minerals from the soil, to elucidate the role roots play in adaptation to drought conditions, and to transfer this knowledge to crop improvement through biotechnology. This project focuses mechanisms of root growth maintenance and root to shoot signaling under water deficits. The research approach is interdisciplinary encompassing whole plant physiology, genetics, genomics, and proteomics.The specific aims are to identify the genes and biochemical networks: controlling the mechanisms of root growth and root to shoot communication under drought through four specific objectives:(1) Characterization of the transcript profiles in elongating and non-elongating regions of roots under water deficit in sensitive and tolerant maize lines, an abscisic acid (ABA)-deficient mutant and near-isogenic lines differing in ABA accumulation. (2) Characterization of the changes in protein profiles, especially cell wall proteins, in the different root regions to identify factors associated with root growth maintenance and tolerance to water deficit. (3) Investigation of the production and transport of root signals to provide a better understanding of root to shoot signaling under drought. (4) Development of genetic and genomic resources for further investigations of root growth and signaling in the field.This knowledge will lead to novel approaches for improving drought tolerance in maize through genetic and metabolic engineering of root functions. All materials will be made publicly available. A Plant Root Genomics Web site will be maintained and integrated with the maize genome database (MaizeDB) at the University of Missouri-Columbia.