Abstract:

Reactive oxygen species (ROS) play a dual role in plant growth, development and responses to numerous environmental stresses: eliciting oxidative damages at high concentration, mediating cellular signalling as second messenger at low concentration. Such a functional switch depends on the equilibrium between ROS production and scavenging, which is delicately monitored by an in vivo binary antioxidative system with both enzymic and nonenzymic components. Among the antioxidative enzymes, plant cytosolic ascorbate peroxidase 1 (APX1) is crucial in cellular redox homeostasis and ROS scavenging network. It has been regarded as an important leverage of ROS roles, and thus given with extensive research interest. This review introduced with emphasis the research progress on plant APX1 in enzymatic characteristics, gene expression and regulation, biological roles, and applications in plant genetic engineering of stress resistance, aiming at providing useful insights for future studies on plant ROS and stress tolerance.

Key words: plant ROS, cytosolic ascorbate peroxidase 1, stress resistance, genetic engineering

摘要：

活性氧(ROS)在植物生长发育和对各种逆境适应过程中扮演双面角色：高浓度下引起氧化损伤、低浓度下发挥第二信使作用，其角色转换取决于其产生和清除之间的平衡状态，并严格受控于体内一套由酶和非酶组分构成的双元抗氧化系统。在抗氧化酶类中，位居细胞质的抗坏血酸过氧化物酶1(APX1)在胞内氧化还原态水平调控中起到关键作用，在ROS清除网络中居于核心地位，已被视作ROS功能的重要杠杆，并因而获得相对最广泛的研究关注。着重介绍了其酶学特性、基因表达和调控、生物学作用及目前主要在植物抗逆基因工程中的应用研究进展，以期为日后植物ROS和抗逆性研究提供有用信息和思路。

关键词: 植物活性氧；APX1；抗逆性；基因工程