title: ABA controls H₂O₂ accumulation through the induction of OsCATB in rice leaves under water stress.
abstract: The production of both ABA and H₂O₂ is induced by drought and can act as signals under stress conditions. We investigated the relationships between ABA, H₂O₂ and catalase (CAT) in rice leaves when rice seedlings were treated with polyethylene glycol as water stress treatment. As a key gene in ABA biosynthesis, OsNCED3 was significantly induced in rice by water stress treatment and such induction preceded the rapid increase in ABA. Water stress inhibited the expression of CATA and CATC but substantially enhanced the expression of CATB. Exogenously applied ABA promoted the expression of CATB also and inhibited the expression of CATC in a concentration-dependent manner. When ABA production was inhibited by using ABA biosynthesis inhibitors nordihydroguaiaretic acid and tungstate, expression of CATB was also subdued while CATC was enhanced under the water stress. Accumulation of H₂O₂ was also reduced when endogenous ABA production was inhibited and showed a correlation with the total activity of catalases. Our results suggest that water stress-induced ABA prevents the excessive accumulation of H₂O₂, through the induction of the expression of CATB gene during water stress.
authors.affiliation: Department of Biology, Hong Kong Baptist University, Hong Kong, China.
authors.forename: Nenghui
authors.initials: N
authors.lastname: Ye
authors.forename: Guohui
authors.initials: G
authors.lastname: Zhu
authors.forename: Yinggao
authors.initials: Y
authors.lastname: Liu
authors.forename: Yingxuan
authors.initials: Y
authors.lastname: Li
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D002374:Catalase / Q000235:genetics / Q000378:metabolism*; D003681:Dehydration / Q000235:genetics / Q000378:metabolism; D049308:Dioxygenases / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism*; D009637:Masoprocol / Q000494:pharmacology; D012275:Oryza / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics; D011092:Polyethylene Glycols / Q000494:pharmacology; D017382:Reactive Oxygen Species; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D017973:Tungsten Compounds / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D017973:Tungsten Compounds; D011092:Polyethylene Glycols; D000040:Abscisic Acid; D009637:Masoprocol; D006861:Hydrogen Peroxide; D002374:Catalase; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase; C045951:tungstate