The integration of the cyclophilin 20-3 and 2-cysteine peroxiredoxin thiol switches in the redox regulatory network of the chloroplast

亲环蛋白20-3和2-半胱氨酸过氧化还原蛋白硫醇开关在叶绿体氧化还原调节网络中的整合

• 批准号: 251861594
• 负责人: Professor Dr. Karl-Josef Dietz
• 金额: --
• 依托单位: Arbeitsgruppe Biochemie und Physiologie der Pflanzen
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/251861594?language=en
• 关键词: integration; cyclophilin; 20; cysteine; peroxiredoxin

The chloroplast contains a physically and functionally interacting regulatory protein module consisting of cyclophilin 20-3 (Cyp20-3), 2-cysteine peroxiredoxin (2-CysPrxA/B), serine acetyl transferase (SERAT2.1) and O-acetylserine thiolyase (OASTL-B), the COPS module. This module controls plastid cysteine synthesis, affects redox homeostasis, interferes with nuclear gene expression and, if compromised, impedes growth performance, particularly under stress. Both Cyp20-3 and 2-CysPrx function as established thiol switches and likely have redox-dependent functions beyond their specific role within the COPS module. This projects aims to understand the physiological integration and redox regulatory significance of the COPS module with emphasis on Cyp20-3. The redox control of the thiol switch protein Cyp20-3 will be studied in vitro to dissect the efficiency of reductants and identify possible oxidants. Structural requirements for the interaction between Cyp20-3, 2-CysPrx, SERAT2.1 and OASTLB will be explored in transfected protoplasts and in Arabidopsis thaliana lines. To this end knockout lines will be complemented with site-directed mutated variants of Cyp20-3 and 2-CysPrx. Emphasis is given to functions of the COPS module in cellular protein homeostasis as indicated by the profound deregulation of transcripts belonging to this particular gene ontology group. The role of Cyp20-3 and 2-CysPrx in oxylipin signaling and carbohydrate metabolism will be scrutinized and linked to novel interactors and involved retrograde signaling from the chloroplast to the nucleus. Furthermore, the project will address the COPS module and its components for their function in balancing chloroplast electron distribution. The overarching hypothesis assumes that the components of the COPS module contribute to the metabolic decision of the plants between investment in growth or defense, and in the distribution of reducing power provided by the photosynthetic electron transport chain to the different consuming pathways.

叶绿体含有一个物理和功能相互作用的调节蛋白模块，包括亲环蛋白20-3（Cyp 20 -3）、2-半胱氨酸过氧化物氧还蛋白（2-CysPrxA/B）、丝氨酸乙酰转移酶（SERAT 2.1）和O-乙酰丝氨酸硫解酶（OASTL-B），即COPS模块。该模块控制质体半胱氨酸合成，影响氧化还原稳态，干扰核基因表达，如果受损，则会阻碍生长性能，特别是在压力下。Cyp 20 -3和2-CysPrx都作为已建立的巯基开关起作用，并且可能具有超出其在COPS模块内的特定作用的氧化还原依赖性功能。该项目旨在了解COPS模块的生理整合和氧化还原调节意义，重点是Cyp 20 -3。将在体外研究巯基开关蛋白Cyp 20 -3的氧化还原控制，以剖析还原剂的效率并识别可能的氧化剂。Cyp 20 -3，2-CysPrx，SERAT 2.1和OASTLB之间的相互作用的结构要求将在转染的原生质体和拟南芥株系中进行探索。为此，敲除系将用Cyp 20 -3和2-CysPrx的定点突变变体补充。重点是给予的COPS模块在细胞蛋白质稳态的功能，所示的深刻放松管制的转录本属于这个特定的基因本体论组。Cyp 20 -3和2-CysPrx在氧脂素信号传导和碳水化合物代谢中的作用将被仔细检查并与新的相互作用物联系起来，并涉及从叶绿体到细胞核的逆行信号传导。此外，该项目还将讨论COPS模块及其组件在平衡叶绿体电子分布方面的功能。总体假设假设的COPS模块的组件之间的投资，在生长或防御，并在分配的光合电子传递链提供的不同的消费途径的还原力的植物的代谢决定。