Kinetics of wound-induced activation of antioxidative enzymes in Oryza sativa: differential activation at different growth stages

• Published in: Plant science (Limerick) Vol. 164; no. 6; pp. 935 - 941
• Main Authors: Chandru, Hema Kumar, Kim, Eunsun, Kuk, Yongin, Cho, Kyoungwon, Han, Oksoo
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01-06-2003; Elsevier Science
• Subjects: Biological and medical sciences; Catalase; Fundamental and applied biological sciences. Psychology; Metabolism; Metabolism. Physicochemical requirements; Peroxidase; Plant physiology and development; Rice; Superoxide dismutase; Wound stress; Wound stress; Cu/Zn–SOD, copper–zinc superoxide dismutase; Catalase; Mn–SOD, manganese superoxide dismutase; Superoxide dismutase; NBT, nitroblue tetrazolium; Peroxidase; DAB, 3,3-diaminobenzidine; ROS, reactive oxygen species; TEMED, tetramethylethylenediamine; Rice; Oxidative stress; Monocotyledones; Growth; Injury; Activation; Antioxidant; Cereal crop; Oryza sativa; Gramineae; Angiospermae; Defense mechanism; Spermatophyta; Kinetics
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/S0168-9452(03)00078-5

Superoxide dismutase, peroxidase and catalase are major antioxidative enzymes that contribute to the oxidative stress response in plants. The activity of these enzymes was measured in wound-stressed rice plants that were wounded at seedling stage, maximum tillering stage or flowering stage. Kinetics of enzyme activity were examined in leaf extracts post-wounding. Superoxide dismutase activity increased rapidly until 6 h after wounding and was maintained at a high level throughout development. Wound stress-induced changes in manganese superoxide dismutase and copper–zinc superoxide dismutase activities were detected using a native activity gel. In contrast, catalase was rapidly deactivated and peroxidase was transiently activated and then deactivated after wounding. However, high peroxidase activity was maintained at maximum tillering stage of development. These observations suggest that rice antioxidant enzymes are differentially activated by wound stress depending on the plant growth stage, and that the antioxidative enzymes are activated by wounding in two phases. The first phase involves activation of superoxide dismutase and peroxidase and rapid deactivation of catalase. The second phase involves deactivation of peroxidase under conditions of severe stress. Deactivation of peroxidase and catalase may lead to accumulation of hydrogen peroxide, which can activate of a series of additional defense mechanisms.