Du Yan-Yan, Wang Peng-Cheng, Chen Jia, Song Chun-Peng
State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China.
J Integr Plant Biol. 2008 Oct;50(10):1318-26. doi: 10.1111/j.1744-7909.2008.00741.x.
In Arabidopsis, catalase (CAT) genes encode a small family of proteins including CAT1, CAT2 and CAT3, which catalyze the decomposition of hydrogen peroxide (H2O2) and play an important role in controlling homeostasis of reactive oxygen species (ROS). Here, we analyze the expression profiles and activities of three catalases under different treatments including drought, cold, oxidative stresses, abscisic acid and salicylic acid in Arabidopsis. Our results reveal that CAT1 is an important player in the removal of H2O2 generated under various environmental stresses. CAT2 and CAT3 are major H2O2 scavengers that contribute to ROS homeostasis in light or darkness, respectively. In addition, CAT2 is activated by cold and drought stresses and CAT3 is mainly enhanced by abscisic acid and oxidative treatments as well as at the senescence stage. These results, together with previous data, suggest that the network of transcriptional control explains how CATs and other scavenger enzymes such as peroxidase and superoxide dismutase may be coordinately regulated during development, but differentially expressed in response to different stresses for controlling ROS homeostasis.
在拟南芥中，过氧化氢酶（CAT）基因编码一个小的蛋白质家族，包括CAT1、CAT2和CAT3，它们催化过氧化氢（H2O2）的分解，并在控制活性氧（ROS）的稳态中发挥重要作用。在此，我们分析了拟南芥在干旱、寒冷、氧化胁迫、脱落酸和水杨酸等不同处理下三种过氧化氢酶的表达谱和活性。我们的结果表明，CAT1是清除各种环境胁迫下产生的H2O2的重要参与者。CAT2和CAT3分别是主要的H2O2清除剂，在光照或黑暗条件下有助于ROS稳态。此外，CAT2被寒冷和干旱胁迫激活，CAT3主要在脱落酸和氧化处理以及衰老阶段增强。这些结果与先前的数据一起表明，转录控制网络解释了CATs和其他清除酶（如过氧化物酶和超氧化物歧化酶）在发育过程中如何协同调节，但在响应不同胁迫以控制ROS稳态时差异表达。
