Changes by cadmium stress in lipid peroxidation and activities of lipoxygenase and antioxidant enzymes in Arabidopsis are associated with extracellular ATP

Abstract

Exposure of Arabidopsis leaves to cadmium (Cd) stress led to an increase in the level of extracellular ATP (eATP). And, Cd stress also caused significant increases in lipid peroxidation and the activities of lipoxygenase (LOX) and antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT). Treatment of Arabidopsis leaves with β,γ-methyleneadenosine 5′-triphosphate (AMP-PCP), which serves as a competitive inhibitor of eATP, dampened the Cd-induced increases of lipid peroxidation and the activities of LOX and antioxidant enzymes. Under Cd stress, the leaves of dorn 1-3 mutant showed lower levels of lipid peroxidation and activities of LOX and antioxidant enzymes compared with those of wild type plants. These results suggest that the changes in lipid peroxidation and activities of LOX and antioxidant enzymes under Cd stress could be associated with eATP.