草酸氧化酶在水稻胚芽鞘衰老中的作用  

Function of Oxalate Oxidase(OxO) during Coleoptile Senescence in Rice(Oryza sativa L.)

作　　者：张建军[1] 赖宇雄[1] 刘娥娥[1] 彭新湘[1] 

机构地区：[1]华南农业大学生命科学学院分子植物生理研究室,广州510642

出　　处：《植物生理学通讯》2010年第10期1040-1044,共5页Plant Physiology Communications

基　　金：广东省博士启动基金(05300955);广东省自然科学基金项目(8151064201000060)

摘　　要：草酸氧化酶(OxO)催化草酸氧化产生CO2和H2O2,其在植物发育及防御过程中可能具有重要作用。本文以水稻品种‘湘糯1号’(‘Xiangnuo 1’)为材料,对胚芽鞘中的OxO及其生理功能进行了研究。结果表明,胚芽鞘中的H2O2含量在其衰老时增加;OxO活性在浸种后96h时较低,之后也迅速增加,在240h达到最高;而可溶性蛋白、O2-·和草酸含量以及过氧化氢酶(CAT)活性则随着胚芽鞘的衰老迅速降低。由于H2O2能够诱导细胞死亡,推测OxO可能通过降解草酸产生H2O2参与胚芽鞘的衰老。Oxalate oxidase（OxO;EC1.2.3.4） catalyzes oxidation of oxalate and yields CO2 and H2O2.It may play important roles in plant growth and defense.In this study,OxO activity,oxalate content and H2O2 production were detected during senescence of coleoptiles in the rice（Oryza sativa） ＇Xiangnuo 1＇ to analysis the possible functions of OxO in senescence of coleoptiles.The results showed that H2O2 content was enhanced with the senescence of coleoptiles.OxO activity was very low at 96 h after imbibition,and then increased significantly and with a maximum at 240 h.Conversely,the levels of soluble protein,oxalate,O2·ˉ and catalase（CAT） activity in coleoptiles were the highest at 96 h,and then decreased.It suggested that OxO might be involved in the senescence of coleoptiles in rice by catalyzing the oxidation of oxalate.

关 键 词：草酸氧化酶 胚芽鞘 衰老 水稻 

分 类 号：Q946[生物学—植物学]