脱落酸与植物细胞的抗氧化防护

水分胁迫是一种影响植物生长发育、限制植物产量的重要胁迫因子.植物能够通过感知刺激、产生和传导信号、启动各种防护机制来响应与适应水分胁迫.植物激素脱落酸(ABA)作为一种胁迫信号,在调节植物对水分胁迫的反应中起着重要的作用.ABA不仅能诱导气孔关闭,而且能诱导编码耐脱水蛋白的基因表达.正在增加的证据显示,ABA增强水分胁迫的耐性与其诱导抗氧化防护系统有关.本文综述了ABA在诱导活性氧(ROS)产生、调节抗氧化酶基因表达以及增强抗氧化防护系统方面的作用,着重讨论了在ABA诱导的抗氧化防护过程中Ca2 、NADPH氧化酶与ROS之间的交谈机制.

Abscisic Acid and Antioxidant Defense in Plant Cells

Water stress is one of the most important environmental factors that affect plant growth and development, and limit plant production. Plants can respond and adapt to water stress by perceiving the stimulus, generating and transmitting the signals, and initiating various defense mechanisms. The plant hormone abscisic acid (ABA), as a stress signal, plays important roles in the regulation of plant responses to water stress. ABA not only regulates water balance by inducing stomatal closure, but also enhances water stress tolerance by inducing the expression of genes that encode dehydration tolerance proteins. Increasing evidence indicates that ABA-enhanced water stress tolerance is related to the induction of antioxidant defense systems by ABA. In this review, recent advances on the roles of ABA in the induction of the generation of reactive oxygen species (ROS), the expression of antioxidant enzyme genes, and the capacity of antioxidant defense systems are presented. Special attention is given to the cross-talk mecha-nisms between Ca²⁺ and ROS that originates from NADPH oxidase in the ABA-induced antioxidant defense in plants.