title: Hydrogen peroxide regulated photosynthesis in C4-pepc transgenic rice.
abstract: In this study, we investigated the photosynthetic physiological basis in 'PC' transgenic rice (Oryza sativa L.), showing high-level expression of the gene encoding C4 phosphoenolpyruvate carboxylase (pepc), by hydrogen peroxide (H2O2). The C4-PEPC gene (pepc) from maize in the transgenic rice plants was checked by PCR. Comparison of yield components and photosynthetic indices between PC and untransformed wild-type (WT) plants indicated that increased yield in PC was associated with higher net photosynthetic rate and higher activities of phosphoenolpyruvate carboxylase (PEPC). Both PC and WT plants were treated with 1 mmol L(-1) abscisic acid (ABA), 0.04% 1-butanol (BA), 2 mmol L(-1) neomycin (NS), or 2 mmol L(-1) diphenyleneiodonium chloride (DPI) to investigate the relationship between photosynthesis and levels of H2O2 and phosphatidic acid. In both PC and WT, ABA induced H2O2 generation and simultaneous decrease in stomatal conductance (g(s)). PC plants treated with BA showed decreased H2O2 content and strongly increased g(s) within 2 h of treatment. Similar results were observed in response to DPI treatment in PC. However, WT did not observe the decrease of H2O2 during the treatments of BA and DPI. The reduced H2O2 content in PC caused by BA treatment differed to that induced by DPI because BA did not inhibit NADPH oxidase activities. While BA induced a larger PEPC activity in PC, and higher catalase activity as well. These results indicated that the regulation of endogenous H2O2 metabolism of PC could be helpful for enhancing photosynthetic capability.
authors: Institute of Food Crops, Jiangsu High Quality Rice R&D Center, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China.
authors: C G
authors: CG
authors: Ren
authors: Institute of Food Crops, Jiangsu High Quality Rice R&D Center, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China. Electronic address: jspplx@jaas.ac.cn.
authors: X
authors: X
authors: Li
authors: Institute of Food Crops, Jiangsu High Quality Rice R&D Center, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, China.
authors: X L
authors: XL
authors: Liu
authors: Institute of Food Crops, Jiangsu High Quality Rice R&D Center, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China.
authors: X D
authors: XD
authors: Wei
authors: College of Life Sciences, Nanjing Normal University, Jiangsu Key Laboratory for microbes and functional genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, Nanjing 210023, China.
authors: C C
authors: CC
authors: Dai
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001483:Base Sequence; D017931:DNA Primers; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008315:Malondialdehyde / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D019255:NADPH Oxidases / Q000378:metabolism; D012275:Oryza / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D010788:Photosynthesis / Q000187:drug effects*; D030821:Plants, Genetically Modified; D016133:Polymerase Chain Reaction
chemical_list: D000975:Antioxidants; D017931:DNA Primers; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D019255:NADPH Oxidases
keywords: 1-Butanol; 1-butanol; 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H tetrazolium hydroxide; ABA; APX; AsA; BA; C(4)pepc; CAT; Chl; DAB; DPI; EDTA; GR; H(2)O(2); MDA; NS; Oryza sativa; P(N); PA; PBS; PC; PEPC; PLC; PLD; POD; PP2C; PPFD; Phospholipase D; Photosynthesis; SEM; SOD; Stomatal conductance; XTT; abscisic acid; ascorbate peroxidase; ascorbic acid; catalase; chlorophyll; diaminobenzidine; diphenyleneiodonium chloride; ethylenediamine tetraacetic acid; g(s); glutathione reductase; malondialdehyde; neomycin; net photosynthetic rate; peroxidase; phoshpate buffer saline; phosphatase 2C; phosphatidic acid; phosphoenolpyruvate carboxylase; phospholipase C; phospholipase D; photosynthetic photon flux density; scanning electron microscope; stomatal conductance; superoxide dismutase; transgenic rice with C(4)pepc