Genetic Analysis of Osmotic Stress Signal Transduction in Plants

植物渗透胁迫信号转导的遗传分析

• 批准号: 0212346
• 负责人: Jian-Kang Zhu
• 金额: $ 39万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0212346&HistoricalAwards=false
• 关键词: Genetic; Analysis; Osmotic; Stress; Signal

Osmotic stress caused by drought and salinity has been a major selective force in plant evolution and an important factor limiting crop productivity. Understanding the mechanisms by which plants detect and respond to osmotic stress is important for basic plant biology and for crop improvement. Previous studies suggested that plant adaptation to osmotic stress is governed by a complex network of regulatory pathways, but most of the key components in these pathways remain to be identified. This project continues previous effort in using Arabidopsis mutants to identify such regulatory components. Several Arabidopsis mutants impaired in osmotic stress-responsive gene expression were recovered from a genetic screen by luciferase imaging using plants that express the RD29A-LUC (firefly luciferase under control of the stress-inducible RD29A promoter) transgene. Some of the mutations have been isolated through map-based cloning, which provided significant new insights into osmotic stress responses in plants. For example, cloning of SAD1 revealed the involvement of RNA metabolism in osmotic stress signaling. This research is based on such findings and is aimed at identifying new regulatory components in osmotic stress signal transduction. Specific aims include the cloning and characterization of two new genetic loci involved in osmotic stress signaling, and the identification of genetic suppressors of existing mutants such as sad1.

干旱和盐分引起的渗透胁迫一直是植物进化中的主要选择力量，也是限制作物产量的重要因素。了解植物检测和响应渗透胁迫的机制对于基础植物生物学和作物改良具有重要意义。以前的研究表明，植物对渗透胁迫的适应是由一个复杂的调控途径网络控制的，但这些途径中的大多数关键成分仍有待确定。该项目延续了先前利用拟南芥突变体来识别此类调控成分的努力。通过利用表达RD29A-Luc(受胁迫诱导的RD29A启动子控制的萤火虫荧光素酶)转基因植物的荧光素酶成像，从遗传筛选中恢复了几个渗透胁迫响应基因表达受损的拟南芥突变体。一些突变已经通过基于图谱的克隆被分离出来，这为植物的渗透胁迫反应提供了重要的新见解。例如，SAD1的克隆揭示了RNA代谢参与渗透胁迫信号转导。这项研究基于这些发现，旨在确定渗透胁迫信号转导中新的调节成分。具体目标包括克隆和鉴定与渗透胁迫信号有关的两个新的遗传位点，以及鉴定现有突变体的遗传抑制基因，如SAD1。