Development Center of Plant Germplasm Resources, College of Life Sciences, Shanghai Normal University, Shanghai, China.
Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, China.
Antioxid Redox Signal. 2020 Jul 1;33(1):35-57. doi: 10.1089/ars.2019.7823. Epub 2020 Mar 12.
Plant chloroplasts generate reactive oxygen species (ROS) during photosynthesis, especially under stresses. The sulfhydryl groups of protein cysteine residues are susceptible to redox modifications, which regulate protein structure and function, and thus different signaling and metabolic processes. The ROS-governed protein thiol redox switches play important roles in chloroplasts. Various high-throughput thiol redox proteomic approaches have been developed, and they have enabled the improved understanding of redox regulatory mechanisms in chloroplasts. For example, the thioredoxin-modulated antioxidant enzymes help to maintain cellular ROS homeostasis. The light- and dark-dependent redox regulation of photosynthetic electron transport, the Calvin/Benson cycle, and starch biosynthesis ensures metabolic coordination and efficient energy utilization. In addition, redox cascades link the light with the dynamic changes of metabolites in nitrate and sulfur assimilation, shikimate pathway, and biosynthesis of fatty acid hormone as well as purine, pyrimidine, and thiamine. Importantly, redox regulation of tetrapyrrole and chlorophyll biosynthesis is critical to balance the photodynamic tetrapyrrole intermediates and prevent oxidative damage. Moreover, redox regulation of diverse elongation factors, chaperones, and kinases plays an important role in the modulation of gene expression, protein conformation, and posttranslational modification that contribute to photosystem II (PSII) repair, state transition, and signaling in chloroplasts. This review focuses on recent advances in plant thiol redox proteomics and redox protein networks toward understanding plant chloroplast signaling, metabolism, and stress responses. Using redox proteomics integrated with biochemical and molecular genetic approaches, detailed studies of cysteine residues, their redox states, cross talk with other modifications, and the functional implications will yield a holistic understanding of chloroplast stress responses.
植物叶绿体在光合作用过程中会产生活性氧（ROS），尤其是在受到胁迫时。蛋白质半胱氨酸残基的巯基易发生氧化还原修饰，从而调节蛋白质的结构和功能，以及不同的信号转导和代谢过程。ROS 调控的蛋白质巯基氧化还原开关在叶绿体中起着重要作用。已经开发了各种高通量巯基氧化还原蛋白质组学方法，这些方法使人们能够更好地理解叶绿体中的氧化还原调控机制。例如，硫氧还蛋白调节的抗氧化酶有助于维持细胞内 ROS 稳态。光合作用电子传递、卡尔文/本森循环和淀粉生物合成的光暗依赖氧化还原调控确保了代谢协调和有效的能量利用。此外，氧化还原级联将光与硝酸盐和硫同化、莽草酸途径以及脂肪酸激素、嘌呤、嘧啶和硫胺素生物合成中的代谢物动态变化联系起来。重要的是，四吡咯和叶绿素生物合成的氧化还原调控对于平衡光动力四吡咯中间体和防止氧化损伤至关重要。此外，各种伸长因子、伴侣蛋白和激酶的氧化还原调控在调节基因表达、蛋白质构象和翻译后修饰方面发挥着重要作用，有助于 PSII 修复、状态转换和信号转导。本文综述了植物巯基氧化还原蛋白质组学和氧化还原蛋白质网络的最新进展，以了解植物叶绿体信号转导、代谢和应激反应。通过将氧化还原蛋白质组学与生化和分子遗传方法相结合，对半胱氨酸残基、其氧化还原状态、与其他修饰的相互作用以及功能意义进行详细研究，将有助于全面理解叶绿体应激反应。
