Function and Organization of the ClpPR Complex in Plastids of Arabidopsis; A Central Protease Essential for Embryogenesis and Seedling Development

拟南芥质体中 ClpPR 复合物的功能和组织；

• 批准号: 0718897
• 负责人: Klaas van Wijk
• 金额: $ 55万
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-10-01 至 2010-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0718897&HistoricalAwards=false
• 关键词: Function; Organization; ClpPR; Complex; Plastids

Intracellular proteases have many functions and must be highly selective in recognizing their substrates. This project concerns the function and substrates of the essential plastid localized Clp protease machinery in Arabidopsis. The ClpPR protease is a double ring shaped complex containing 10 different ClpPR proteins, most of which are essential for embryogenesis or seedling development. Attached to the barrel are small ClpS1,2 proteins with unknown function and unique to photosynthetic organisms. Clp substrates and substrate recognition mechanisms in plastids are unknown. The objectives are: i) to determine which ClpPR proteins are essential for embryogenesis or seedling development, by completion of genetic analysis of ClpPR mutants. Possible functional redundancy within the ClpR family will be further tested, ii) to carry out targeted biochemical experiments using the clpr2-1 mutant to understand the role of ClpPR complex in plastid gene expression and protein homeostasis, iii) to determine the composition of the asymmetric structure of the ClpPRS complex by biochemical analysis of purified Clp complexes, iv) to identify Clp protease substrates, their degradation signals and specificity of chaperone delivery systems to the ClpPR core complex.Broader impacts: This project will help to determine the molecular function and organization of the Clp protease system, as well as its substrates and substrate recognition mechanisms. Understanding the role of the Clp proteolytic machinery and substrate recognition signals is also critical to control protein stability with the objective to improve the plastid as the site for overproduction of foreign proteins with e.g nutritional or pharmaceutical value (e.g. edible vaccines). The research will provide multi-disciplinary training in plant molecular genetics and biochemistry at the undergraduate, graduate and post-doctoral levels. The PI and co-PI will also participate in curriculum development workshops for high school teachers to develop genomics-based modules for the classroom.

细胞内蛋白酶具有多种功能，并且在识别其底物时必须具有高度选择性。该项目涉及拟南芥中重要质体局部 Clp 蛋白酶机制的功能和底物。 ClpPR 蛋白酶是一种双环形复合物，含有 10 种不同的 ClpPR 蛋白，其中大多数对于胚胎发生或幼苗发育至关重要。附着在桶上的是小的 ClpS1,2 蛋白质，其功能未知，是光合生物所特有的。质体中的 Clp 底物和底物识别机制尚不清楚。目标是： i) 通过完成 ClpPR 突变体的遗传分析，确定哪些 ClpPR 蛋白对于胚胎发生或幼苗发育至关重要。将进一步测试 ClpR 家族内可能的功能冗余，ii) 使用 clpr2-1 突变体进行有针对性的生化实验，以了解 ClpPR 复合物在质体基因表达和蛋白质稳态中的作用，iii) 确定不对称的组成通过对纯化的 Clp 复合物进行生化分析来确定 ClpPRS 复合物的结构，iv) 识别 Clp 蛋白酶底物、其降解信号以及伴侣递送系统对 ClpPR 核心的特异性更广泛的影响：该项目将有助于确定 Clp 蛋白酶系统的分子功能和组织，及其底物和底物识别机制。了解 Clp 蛋白水解机制和底物识别信号的作用对于控制蛋白质稳定性也至关重要，目的是改善质体作为具有营养或药用价值（例如可食用疫苗）的外来蛋白质过量生产的位点。该研究将为本科生、研究生和博士后提供植物分子遗传学和生物化学方面的多学科培训。 PI 和 co-PI 还将参加高中教师的课程开发研讨会，为课堂开发基于基因组学的模块。