Activation of Plant Stress-Responsive MAP Kinases Induces Cyanide - its Role in Reactive Oxygen Species Generation and Hypersensitive Cell Death

植物应激反应性 MAP 激酶的激活诱导氰化物 - 其在活性氧生成和过敏性细胞死亡中的作用

• 批准号: 0743957
• 负责人: Shuqun Zhang
• 金额: $ 45万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2012-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0743957&HistoricalAwards=false
• 关键词: Activation; Plant; Stress; Responsive; MAP

Mitogen-activated protein kinase (MAPK, or MPK) cascades are conserved signaling modules that play vital roles in all eukaryotic organisms. Arabidopsis MPK3 and MPK6, as well as their functional equivalents in other species, are implicated in plant disease resistance. However, the underlying mechanism is unclear. Recently, it was discovered that activation of MPK3 and MPK6 induces cyanide accumulation, which leads to the generation of reactive oxygen species (ROS) in chloroplasts and cell death during the hypersensitive response. In this project, the investigators will use a combination of physiological, biochemical, and molecular genetic approaches to understand the regulation of cyanide accumulation during plant defense response and to generate plants with either elevated or reduced cyanide accumulation. Phenotypic analyses of these plants will provide in vivo gain- and loss-of-functional evidence to establish cyanide as a new regulatory/signaling molecule in plants. Cyanide is a co-product of ethylene biosynthesis. As a plant hormone, ethylene has been the focus of much study, its role in plant physiological and developmental processes, as well as the mechanisms of ethylene action have been investigated extensively. However, cyanide as a regulatory molecule in plants has been mostly ignored, despite its obvious biological effects on a number of critical enzymes and processes in cells. Broader impacts. The use of a combinatory approach in this project will provide an excellent training environment for students and post-docs. Students (both graduate and undergraduate) and post-docs from under-represented groups will be actively recruited though participation in institutional programs which reach out to such scientists. Cyanide is a potent inhibitor of various activities in chloroplasts and mitochondria, two organelles known as cellular 'power plants'. Understanding the regulation of cyanide accumulation and its functions in energy conversion, ROS generation, and HR cell death may lead to the generation of crops with enhanced yield under stress conditions. This is important for agriculture to produce enough food/feed and harvestable energy to meet an increasing demand.

丝裂原激活蛋白激酶（MAPK 或 MPK）级联是保守的信号模块，在所有真核生物中发挥着重要作用。拟南芥 MPK3 和 MPK6 以及它们在其他物种中的功能等同物与植物抗病性有关。然而，其根本机制尚不清楚。最近发现，MPK3和MPK6的激活会诱导氰化物积累，从而导致叶绿体中活性氧（ROS）的产生，并在过敏反应过程中导致细胞死亡。在该项目中，研究人员将结合使用生理学、生化和分子遗传学方法来了解植物防御反应期间氰化物积累的调节，并培育氰化物积累升高或降低的植物。这些植物的表型分析将提供体内功能获得和丧失的证据，以确定氰化物作为植物中新的调节/信号分子。氰化物是乙烯生物合成的副产品。乙烯作为一种植物激素一直是人们研究的热点，其在植物生理和发育过程中的作用以及乙烯的作用机制已被广泛研究。然而，氰化物作为植物中的调节分子却大多被忽视，尽管它对细胞中的许多关键酶和过程具有明显的生物学作用。更广泛的影响。该项目采用组合方法将为学生和博士后提供良好的培训环境。来自代表性不足群体的学生（研究生和本科生）和博士后将通过参与接触这些科学家的机构项目来积极招募。氰化物是叶绿体和线粒体（这两种被称为细胞“发电厂”的细胞器）中各种活动的有效抑制剂。了解氰化物积累的调节及其在能量转换、ROS 生成和 HR 细胞死亡中的功能可能会导致在胁迫条件下产生产量提高的作物。这对于农业生产足够的粮食/饲料和可收获能源以满足不断增长的需求非常重要。