Involvement of polyamine oxidase in abscisic acid-induced cytosolic antioxidant defense in leaves of maize.
Using pharmacological and biochemical approaches, the role of maize polyamine oxidase (MPAO) in abscisic acid (ABA)-induced antioxidant defense in leaves of maize (Zea mays L.) plants was investigated. Exogenous ABA treatment enhanced the expression of the MPAO gene and the activities of apoplastic MPAO. Pretreatment with two different inhibitors for apoplastic MPAO partly reduced hydrogen peroxide (H2O2) accumulation induced by ABA and blocked the ABA-induced expression of the antioxidant genes superoxide dismutase 4 and cytosolic ascorbate peroxidase and the activities of the cytosolic antioxidant enzymes. Treatment with spermidine, the optimum substrate of MPAO, also induced the expression and the activities of the antioxidant enzymes, and the upregulation of the antioxidant enzymes was prevented by two inhibitors of MPAO and two scavengers of H2O2. These results suggest that MPAO contributes to ABA-induced cytosolic antioxidant defense through H2O2, a Spd catabolic product.
Xue
Beibei
B
College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Zhang
Aying
A
Jiang
Mingyi
M
D000040:Abscisic Acid / Q000494:pharmacology*; D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000494:pharmacology; D003600:Cytosol / Q000187:drug effects / Q000201:enzymology* / Q000276:immunology*; D003959:Diamines / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006146:Guanidines / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000378:metabolism; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D013095:Spermidine / Q000494:pharmacology; D013194:Staining and Labeling; D013890:Thiourea / Q000031:analogs & derivatives / Q000494:pharmacology; D013997:Time Factors; D003313:Zea mays / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D000097667:Polyamine Oxidase
D000040:Abscisic Acid; D000975:Antioxidants; D002374:Catalase; D003959:Diamines; D006146:Guanidines; D006861:Hydrogen Peroxide; D000587:Oxidoreductases Acting on CH-NH Group Donors; D013095:Spermidine; D013890:Thiourea; D000097667:Polyamine Oxidase; C016417:1,12-dodecamethylenediamine; C038983:1,3-dimethylthiourea; C012343:guazatine