title: The rice thylakoid membrane-bound ascorbate peroxidase OsAPX8 functions in tolerance to bacterial blight.
abstract: Thylakoid membrane-bound ascorbate peroxidase (tAPX) is a major H2O2-scavenging enzyme. To clarify its functions in tolerance to rice bacterial blight, we produced rice lines overexpressing and suppressing tAPX (OsAPX8). The overexpressing lines exhibited increased tolerance to bacterial pathogen. The RNA interference (RNAi) lines were considerably more sensitive than the control plant. Further analysis of the H2O2 content in these transgenic plants indicated that the H2O2 accumulation of OsAPX8-overexpressing plants was considerably less than that of wild-type and RNAi plants upon challenge with bacterial pathogen. Interestingly, H2O2 was the most important factor for the serious leaf dehydration and withering of rice without major resistance genes and was not the cause of hypersensitivity. It addition, wall tightening or loosening can occur according to the level of H2O2. In addition, OsAPX8 interacted with the susceptibility protein Os8N3/Xa13, and their binding repressed the reaction of OsAPX8 in tolerance to bacterial blight.
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Guanghuai
authors.initials: G
authors.lastname: Jiang
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Dedong
authors.initials: D
authors.lastname: Yin
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Jiying
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Honglin
authors.initials: H
authors.lastname: Chen
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Lequn
authors.initials: L
authors.lastname: Guo
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Lihuang
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Wenxue
authors.initials: W
authors.lastname: Zhai
mesh_terms: D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism*; D004198:Disease Susceptibility; D020868:Gene Silencing; D006861:Hydrogen Peroxide / Q000032:analysis; D012275:Oryza / Q000201:enzymology* / Q000235:genetics / Q000276:immunology*; D010935:Plant Diseases / Q000276:immunology*; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000276:immunology; D011485:Protein Binding; D025941:Protein Interaction Mapping; D020524:Thylakoids / Q000201:enzymology*
chemical_list: D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases