Redox Regulation of mRNA Destablization and Gene Transcription During the Defense Response in Plants

植物防御反应过程中 mRNA 失稳和基因转录的氧化还原调节

• 批准号: 9729537
• 负责人: Mona Mehdy
• 金额: $ 6万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-15 至 2000-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9729537&HistoricalAwards=false
• 关键词: Redox; Regulation; mRNA; Destablization; Gene

9729537 Mehdy Plant disease resistance mechanisms include the rapid production of active oxygen species in response to pathogen attack. Active oxygen species such as hydrogen peroxide serve as secondary messengers to mobilize changes in the expression of some defense-related genes. Dr. Mehdy and her associate's prior studies of cultured dwarf French bean cells treated with fungal elicitor provided evidence that hydrogen peroxide from the oxidative burst results in the rapid degradation of a normally stable cell wall proline-rich protein mRNA, PvPRP1. The ensuing reduced synthesis of the PvPRP1 protein is likely to contribute to remodeling of the cell wall to make it more resistant to pathogen attack. To understand the mechanism of PvPRP1 mRNA downregulation, Dr. Mehdy and her associates will focus on the biochemical characterization and cloning of a 50-kD RNA binding protein that specifically binds to the PvPRP1 MRNA. Since the purified protein requires reduced sulfhydryl group(s) for RNA binding activity, specific cellular reductants that may play a regulatory role will be investigated in in vitro assays. Thirdly, Dr. Mehdy and her associates will begin to use the genetically amenable legume species, Medicago truncatula, to screen for mutations in components that lie between pathogen-induced hydrogen peroxide and regulation of PvPRP1 mRNA expression. This study will contribute to understanding signalling pathways involving active oxygen species and suggest strategies for improving disease resistance in crops.

9729537方法植物抗病机制包括快速产生活性氧以响应病原体的攻击。 活性氧物质如过氧化氢作为第二信使，调动一些防御相关基因表达的变化。 Mehdy博士和她的同事先前对用真菌激发子处理的矮菜豆细胞的研究提供了证据，证明氧化爆发产生的过氧化氢导致通常稳定的细胞壁富含脯氨酸的蛋白质mRNA PvPRP1的快速降解。 随后PvPRP1蛋白合成的减少可能有助于细胞壁的重塑，使其更能抵抗病原体的攻击。 为了了解PvPRP1 mRNA下调的机制，Mehdy博士和她的同事将专注于特异性结合PvPRP1 mRNA的50 kD RNA结合蛋白的生物化学表征和克隆。 由于纯化的蛋白质需要还原的巯基才能具有RNA结合活性，因此将在体外试验中研究可能发挥调节作用的特定细胞还原剂。 第三，Mehdy博士和她的同事将开始使用遗传上适合的豆类物种，蒺藜苜蓿，来筛选病原体诱导的过氧化氢和PvPRP 1 mRNA表达调控之间的成分突变。 这项研究将有助于了解涉及活性氧的信号通路，并提出提高作物抗病性的策略。