Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Harbin 150040, China.
Development Centre of Plant Germplasm Resources, College of Life and Environmental Sciences, Shanghai Normal University, Shanghai 200234, China.
Int J Mol Sci. 2017 Oct 2;18(10):2085. doi: 10.3390/ijms18102085.
Hydrogen peroxide (H₂O₂) is one of the most abundant reactive oxygen species (ROS), which plays dual roles as a toxic byproduct of cell metabolism and a regulatory signal molecule in plant development and stress response. × is an important cultivated forest species with resistance to cold, drought, insect and disease, and also a key model plant for forest genetic engineering. In this study, H₂O₂ response in leaves was investigated using physiological and proteomics approaches. The seedlings of 50-day-old under H₂O₂ stress exhibited stressful phenotypes, such as increase of in vivo H₂O₂ content, decrease of photosynthetic rate, elevated osmolytes, antioxidant accumulation, as well as increased activities of several ROS scavenging enzymes. Besides, 81 H₂O₂-responsive proteins were identified in the poplar leaves. The diverse abundant patterns of these proteins highlight the H₂O₂-responsive pathways in leaves, including 14-3-3 protein and nucleoside diphosphate kinase (NDPK)-mediated signaling, modulation of thylakoid membrane structure, enhancement of various ROS scavenging pathways, decrease of photosynthesis, dynamics of proteins conformation, and changes in carbohydrate and other metabolisms. This study provides valuable information for understanding H₂O₂-responsive mechanisms in leaves of × .
过氧化氢（H₂O₂）是最丰富的活性氧（ROS）之一，它在细胞代谢的有毒副产物和植物发育和应激反应的调节信号分子中发挥双重作用。×是一种具有抗寒、抗旱、抗虫、抗病能力的重要造林树种，也是林木遗传工程的关键模式植物。本研究采用生理和蛋白质组学方法研究了×叶片中过氧化氢的反应。在过氧化氢胁迫下，50 天大的×幼苗表现出应激表型，如体内过氧化氢含量增加、光合速率降低、渗透物升高、抗氧化剂积累以及几种 ROS 清除酶活性升高。此外，在杨树叶中还鉴定出 81 种过氧化氢响应蛋白。这些蛋白质的丰富模式多样，突出了叶片中过氧化氢响应途径，包括 14-3-3 蛋白和核苷二磷酸激酶（NDPK）介导的信号转导、类囊体膜结构的调节、各种 ROS 清除途径的增强、光合作用的降低、蛋白质构象的动态变化以及碳水化合物和其他代谢物的变化。该研究为理解×叶片中过氧化氢响应机制提供了有价值的信息。
