Involvement of Polyamine Oxidase in Abscisic Acidinduced Cytosolic Antioxidant Defense in Leaves of Maize  

作　　者：Beibei Xue Aying Zhang Mingyi Jiang 

机构地区：[1]College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China

出　　处：《Journal of Integrative Plant Biology》2009年第3期225-234,共10页植物学报（英文版）

基　　金：Supported by the Science Foundation for New Teachers of Doctoral Subject Point of the Ministry of Education of China (20070307018).

摘　　要：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 （H202） 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 H202. These results suggest that MPAO contributes to ABA-induced cytosolic antioxidant defense through H202, a Spd catabolic product.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 （H202） 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 H202. These results suggest that MPAO contributes to ABA-induced cytosolic antioxidant defense through H202, a Spd catabolic product.

关 键 词：abscisic acid cytosolic antioxidant defense hydrogen peroxide polyamine oxidase Zea mays. 

分 类 号：Q946.5[生物学—植物学] Q945.78