细胞氧化还原状态在植物对干旱胁迫响应与适应中的作用

Roles of Intracellular Redox State in Response and Adaptation of Plants to Drought Stress

植物细胞在正常的生理状况下,存在着氧化还原状态的动态平衡,对维持生物大分子正常的理化性质、酶活性以及植物的正常代谢具有重要作用。在干旱胁迫下,植物细胞会发生氧化还原代谢的紊乱,导致植物细胞中活性氧大量积累,进而对植物形成氧化胁迫。氧化胁迫的持续,会使细胞氧化还原状态失衡,最终造成植物大分子(例如DNA、蛋白质、脂质等)的氧化损伤,甚至导致植物细胞的死亡。在植物细胞中,主要通过蛋白巯基系统、谷胱甘肽、抗坏血酸以及吡啶核酸[NAD(H)和NADP(H)]等实现对植物细胞氧化还原状态的调节。阐述植物细胞内氧化还原状态平衡的调控,及其在植物对干旱胁迫响应与适应过程中的作用。

Under the normal physiological conditions,there is a dynamic equilibrium of redox state in plant cells,which plays an important role in maintaining the normal physicochemical properties,enzyme activities,and normal metabolism of the biological macromolecules.Under drought stress,plant cells will undergo disorder of redox metabolism,resulting in a large accumulation of reactive oxygen species in the plant cells,thus leading to oxidative stress on plants.The persistence of oxidative stress will cause the redox state of the cells to be unbalanced,eventually cause oxidative damage to plant macromolecules(such as DNA,proteins,lipids,etc.)and even death of plant cells.The redox status in plant cells was mainly controlled by the protein sulfhydryl system,glutathione,ascorbic acid,and pyridine nucleic acids[NAD(H)and NADP(H)].Regulation of balance of intracellular redox state and the roles of the redox status in response and adaptation of plants to drought stress were reviewed.