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Saini D, Bapatla RB, Vemula CK, Gahir S, Bharath P, Gupta KJ, Raghavendra AS. Moderate modulation by S-nitrosoglutathione of photorespiratory enzymes in pea (Pisum sativum) leaves, compared to the strong effects of high light. PROTOPLASMA 2024; 261:43-51. [PMID: 37421536 DOI: 10.1007/s00709-023-01878-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 06/28/2023] [Indexed: 07/10/2023]
Abstract
When plants are exposed to water stress, photosynthesis is downregulated due to enhanced reactive oxygen species (ROS) and nitric oxide (NO). In contrast, photorespiratory metabolism protected photosynthesis and sustained yield. Modulation of photorespiration by ROS was established, but the effect of NO on photorespiratory metabolism was unclear. We, therefore, examined the impact of externally added NO by using S-nitrosoglutathione (GSNO), a natural NO donor, in leaf discs of pea (Pisum sativum) under dark or light: moderate or high light (HL). Maximum NO accumulation with GSNO was under high light. The presence of 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), a NO scavenger, prevented the increase in NO, confirming the release of NO in leaves. The increase in S-nitrosothiols and tyrosine-nitrated proteins on exposure to GSNO confirmed the nitrosative stress in leaves. However, the changes by GSNO in the activities and transcripts of five photorespiratory enzymes: glycolate oxidase, hydroxypyruvate reductase, catalase, glycerate kinase, and phosphoglycolate phosphatase activities were marginal. The changes in photorespiratory enzymes caused by GSNO were much less than those with HL. Since GSNO caused only mild oxidative stress, we felt that the key modulator of photorespiration might be ROS, but not NO.
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Affiliation(s)
- Deepak Saini
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Ramesh B Bapatla
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | | | - Shashibhushan Gahir
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Pulimamidi Bharath
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | | | - Agepati S Raghavendra
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India.
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Sunil B, Rajsheel P, Aswani V, Bapatla RB, Talla SK, Raghavendra AS. Photosynthesis is sensitive to nitric oxide and respiration sensitive to hydrogen peroxide: Studies with pea mesophyll protoplasts. JOURNAL OF PLANT PHYSIOLOGY 2020; 246-247:153133. [PMID: 32065920 DOI: 10.1016/j.jplph.2020.153133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 01/27/2020] [Accepted: 02/01/2020] [Indexed: 05/27/2023]
Abstract
Reports on the effect of nitric oxide (NO) or reactive oxygen species (ROS) on photosynthesis and respiration in leaf tissues are intriguing; therefore, the effects of exogenous addition of sodium nitroprusside (SNP, releases NO) or H2O2 on the photosynthetic O2 evolution and respiratory O2 uptake by mesophyll protoplasts in pea (Pisum sativum) were evaluated in the present study. Low concentrations of SNP or H2O2 were used to minimize nonspecific effects. The effects of NO or H2O2 on respiration and photosynthesis were different. The presence of NO decreased the rate of photosynthesis but caused a marginal stimulation of dark respiration. Conversely, externally administered H2O2 drastically decreased the rate of respiration but only slightly decreased photosynthesis. The PS I activity was more sensitive to NO than PS II. On the other hand, 100 μM H2O2 had no effect on the photochemical reactions of either PS I or PS II. The sensitivity of photosynthesis to antimycin A or SHAM (reflecting the interplay between chloroplasts and mitochondria) was not affected by NO. By contrast, H2O2 markedly decreased the sensitivity of photosynthesis to antimycin A and SHAM. It can be concluded that chloroplasts are the primary targets of NO, while mitochondria are the primary targets of ROS in plant cells. We propose that H2O2 can be an important signal to modulate the crosstalk between chloroplasts and mitochondria.
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Affiliation(s)
- Bobba Sunil
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Pidakala Rajsheel
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Vetcha Aswani
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Ramesh B Bapatla
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Sai K Talla
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India
| | - Agepati S Raghavendra
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
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Huo J, Huang D, Zhang J, Fang H, Wang B, Wang C, Ma Z, Liao W. Comparative Proteomic Analysis during the Involvement of Nitric Oxide in Hydrogen Gas-Improved Postharvest Freshness in Cut Lilies. Int J Mol Sci 2018; 19:E3955. [PMID: 30544843 PMCID: PMC6320913 DOI: 10.3390/ijms19123955] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/05/2018] [Accepted: 12/06/2018] [Indexed: 11/16/2022] Open
Abstract
Our previous studies suggested that both hydrogen gas (H₂) and nitric oxide (NO) could enhance the postharvest freshness of cut flowers. However, the crosstalk of H₂ and NO during that process is unknown. Here, cut lilies (Lilium "Manissa") were used to investigate the relationship between H₂ and NO and to identify differentially accumulated proteins during postharvest freshness. The results revealed that 1% hydrogen-rich water (HRW) and 150 μM sodium nitroprusside (SNP) significantly extended the vase life and quality, while NO inhibitors suppressed the positive effects of HRW. Proteomics analysis found 50 differentially accumulated proteins in lilies leaves which were classified into seven functional categories. Among them, ATP synthase CF1 alpha subunit (chloroplast) (AtpA) was up-regulated by HRW and down-regulated by NO inhibitor. The expression level of LlatpA gene was consistent with the result of proteomics analysis. The positive effect of HRW and SNP on ATP synthase activity was inhibited by NO inhibitor. Meanwhile, the physiological-level analysis of chlorophyll fluorescence and photosynthetic parameters also agreed with the expression of AtpA regulated by HRW and SNP. Altogether, our results suggested that NO might be involved in H₂-improved freshness of cut lilies, and AtpA protein may play important roles during that process.
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Affiliation(s)
- Jianqiang Huo
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Dengjing Huang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Jing Zhang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Hua Fang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Bo Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Chunlei Wang
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Zhanjun Ma
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
| | - Weibiao Liao
- College of Horticulture, Gansu Agricultural University, Lanzhou 730070, China.
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Tang Y, Li X, Lu W, Wei X, Zhang Q, Lv C, Song N. Enhanced photorespiration in transgenic rice over-expressing maize C 4 phosphoenolpyruvate carboxylase gene contributes to alleviating low nitrogen stress. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 130:577-588. [PMID: 30114676 DOI: 10.1016/j.plaphy.2018.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/25/2018] [Accepted: 08/08/2018] [Indexed: 05/27/2023]
Abstract
The objective of this study was to reveal the physiological and molecular mechanisms of low-nitrogen (N) tolerance in transgenic plant lines containing C4 phosphoenolpyruvate carboxylase (C4-PEPC) gene. The transgenic rice lines only over-expressing the maize C4-PEPC) (PC) and their untransformed wild type, Kitaake (WT), were used in this study. At different N levels, the dry weight, total N content, carbon and N levels, photorespiration-related enzymatic activities, gene expression levels and photorespiration-related product accumulations were measured, as were the transgenic lines' agronomic traits. The PC line, having lower total N and higher soluble sugar contents, was more tolerant to low-N stress than WT, which was consistent with its higher PEPC and lower N-assimilation-related enzyme activity levels. The photosynthetic parameters, enzymatic activity levels, transcripts and products related to photorespiration in PC were also greater than in WT under low-N conditions. This study showed that increased carbon levels in transgenic rice lines overexpressing C4-PEPC could help regulate the photorespiratory pathway under low-N conditions, conferring low-N tolerance and a higher grain yield per plant.
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Affiliation(s)
- Yuting Tang
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China; Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Xia Li
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China; Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; College of Biology and Environment, Nanjing Forestry University, Nanjing, 210037, China.
| | - Wei Lu
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaodong Wei
- Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Qijun Zhang
- Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Chuangen Lv
- Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Ningxi Song
- Institute of Food Crops, Jiangsu Rice Engineering Research Center, National Center for Rice Improvement (Nanjing), Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; College of Biology and Environment, Nanjing Forestry University, Nanjing, 210037, China
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Baena G, Feria AB, Echevarría C, Monreal JA, García-Mauriño S. Salinity promotes opposite patterns of carbonylation and nitrosylation of C 4 phosphoenolpyruvate carboxylase in sorghum leaves. PLANTA 2017; 246:1203-1214. [PMID: 28828537 DOI: 10.1007/s00425-017-2764-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
Carbonylation inactivates sorghum C 4 PEPCase while nitrosylation has little impact on its activity but holds back carbonylation. This interplay could be important to preserve photosynthetic C4 PEPCase activity in salinity. Previous work had shown that nitric acid (NO) increased phosphoenolpyruvate carboxylase kinase (PEPCase-k) activity, promoting the phosphorylation of phosphoenolpyruvate carboxylase (PEPCase) in sorghum leaves (Monreal et al. in Planta 238:859-869, 2013b). The present work investigates the effect of NO on C4 PEPCase in sorghum leaves and its interplay with carbonylation, an oxidative modification frequently observed under salt stress. The PEPCase of sorghum leaves could be carbonylated in vitro and in vivo, and this post-translational modification (PTM) was accompanied by a loss of its activity. Similarly, PEPCase could be S-nitrosylated in vitro and in vivo, and this PTM had little impact on its activity. The S-nitrosylated PEPCase showed increased resistance towards subsequent carbonylation, both in vitro and in vivo. Under salt shock, carbonylation of PEPCase increased in parallel with decreased S-nitrosylation of the enzyme. Subsequent increase of S-nitrosylation was accompanied by decreased carbonylation. Taken together, the results suggest that S-nitrosylation could contribute to maintain C4 PEPCase activity in stressed sorghum plants. Thus, salt-induced NO synthesis would be protecting photosynthetic PEPCase activity from oxidative inactivation while promoting its phosphorylation, which will guarantee its optimal functioning in suboptimal conditions.
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Affiliation(s)
- Guillermo Baena
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes nº 6, 41012, Seville, Spain
| | - Ana B Feria
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes nº 6, 41012, Seville, Spain
| | - Cristina Echevarría
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes nº 6, 41012, Seville, Spain
| | - José A Monreal
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes nº 6, 41012, Seville, Spain
| | - Sofía García-Mauriño
- Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes nº 6, 41012, Seville, Spain.
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Liu X, Li X, Dai C, Zhou J, Yan T, Zhang J. Improved short-term drought response of transgenic rice over-expressing maize C 4 phosphoenolpyruvate carboxylase via calcium signal cascade. JOURNAL OF PLANT PHYSIOLOGY 2017; 218:206-221. [PMID: 28888162 DOI: 10.1016/j.jplph.2017.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 08/22/2017] [Accepted: 08/22/2017] [Indexed: 06/07/2023]
Abstract
To understand the link between long-term drought tolerance and short-term drought responses in plants, transgenic rice (Oryza sativa L.) plants over-expressing the maize C4-pepc gene encoding phosphoenolpyruvate carboxylase (PC) and wild-type (WT) rice plants were subjected to PEG 6000 treatments to simulate drought stress. Compared with WT, PC had the higher survival rate and net photosynthetic rate after 16days of drought treatment, and had higher relative water content in leaves after 2h of drought treatment as well, conferring drought tolerance. WT accumulated higher amounts of malondialdehyde, superoxide radicals, and H2O2 than PC under the 2-h PEG 6000 treatment, indicating greater damages in WT. Results from pretreatments with a Ca2+ chelator and/or antagonist showed that the regulation of the early drought response in PC was Ca2+-dependent. The NO and H2O2 levels in PC lines were also up-regulated via Ca2+ signals, indicating that Ca2+ in PC lines also reacted upstream of NO and H2O2. 2-h drought treatment increased the transcripts of CPK9 and CPK4 in PC via positive up-regulation of Ca2+. The transcripts of NAC6 [NACs (NAM, ATAF1, ATAF2, and CUC2)] and bZIP60 (basic leucine zipper, bZIP) were up-regulated, but those of DREB2B (dehydration-responsive element-binding protein, DREB) were down-regulated, both via Ca2+ signals in PC. PEPC activity, expressions of C4-pepc, and the antioxidant enzyme activities in PC lines were up-regulated via Ca2+. These results indicated that Ca2+ signals in PC lines can up-regulate the NAC6 and bZIP60 and the downstream targets for early drought responses, conferring drought tolerance for the long term.
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Affiliation(s)
- Xiaolong Liu
- Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R and D Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xia Li
- Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R and D Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China.
| | - Chuanchao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Jiayu Zhou
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing 210023, PR China
| | - Ting Yan
- Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R and D Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Jinfei Zhang
- Institute of Food Crops, Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R and D Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing 210014, PR China
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Zhang C, Li X, He Y, Zhang J, Yan T, Liu X. Physiological investigation of C 4-phosphoenolpyruvate-carboxylase-introduced rice line shows that sucrose metabolism is involved in the improved drought tolerance. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2017; 115:328-342. [PMID: 28415033 DOI: 10.1016/j.plaphy.2017.03.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/22/2017] [Accepted: 03/27/2017] [Indexed: 06/07/2023]
Abstract
We compared the drought tolerance of wild-type (WT) and transgenic rice plants (PC) over-expressing the maize C4PEPC gene, which encodes phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) gene, and evaluated the roles of saccharide and sugar-related enzymes in the drought response. Pot-grown seedlings were subjected to real drought conditions outdoors, and the yield components were compared between PC and untransformed wild-type (WT) plants. The stable yield from PC plants was associated with higher net photosynthetic rate under the real drought treatment. The physiological characters of WT and PC seedlings under a simulated drought treatment (25% (w/v) polyethylene glycol-6000 for 3 h; PEG 6000 treatment) were analyzed in detail for the early response of drought. The relative water content was higher in PC than in WT, and PEPC activity and the C4-PEPC transcript level in PC were elevated under the simulated drought conditions. The endogenous saccharide responses also differed between PC and WT under simulated drought stress. The higher sugar decomposition rate in PC than in WT under drought analog stress was related to the increased activities of sucrose phosphate synthase, sucrose synthase, acid invertase, and neutral invertase, increased transcript levels of VIN1, CIN1, NIN1, SUT2, SUT4, and SUT5, and increased activities of superoxide dismutase and peroxidase in the leaves. The greater antioxidant defense capacity of PC and its relationship with saccharide metabolism was one of the reasons for the improved drought tolerance. In conclusion, PEPC effectively alleviated oxidative damage and enhanced the drought tolerance in rice plants, which were more related to the increase of the endogenous saccharide decomposition. These findings show that components of C4 photosynthesis can be used to increase the yield of rice under drought conditions.
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Affiliation(s)
- Chen Zhang
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xia Li
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China.
| | - Yafei He
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China
| | - Jinfei Zhang
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China
| | - Ting Yan
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiaolong Liu
- Institute of Food and Crops, Jiangsu Academy of Agricultural Sciences Nanjing 210014, PR China
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Liu X, Li X, Zhang C, Dai C, Zhou J, Ren C, Zhang J. Phosphoenolpyruvate carboxylase regulation in C4-PEPC-expressing transgenic rice during early responses to drought stress. PHYSIOLOGIA PLANTARUM 2017; 159:178-200. [PMID: 27592839 DOI: 10.1111/ppl.12506] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/14/2016] [Accepted: 08/05/2016] [Indexed: 05/11/2023]
Abstract
Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) has important functions in C4 photosynthesis and biosynthesis of intermediate metabolites. In this study, the drought resistance of C4-PEPC-expressing transgenic rice (Oryza sativa, line PC) plants was assessed using simulated drought conditions [i.e. polyethylene glycol (PEG)-6000 treatment]. The dry weight of PC plants was higher than that of wild-type (WT) plants following treatment with 15% PEG-6000 for 16 days. Furthermore, the water use efficiency, relative water content and proline content in PC plants were higher than those of WT plants, as were C4-PEPC activity and transcript levels following treatment with 5% PEG-6000 for 2 h. The protein kinase activities and transcript levels of sucrose non-fermenting-1-related protein kinases (SnRKs) genes, such as SnRK1a, OsK24 and OsK35 were also higher in PC plants than in WT plants following treatment with 5% PEG-6000 for 2 h. Additionally, phosphoenolpyruvate carboxylase kinase (PPCK, EC 4.1.1.32) activities and transcript levels (e.g. PPCK1 and PPCK2) increased following drought treatment. These changes were regulated by signaling molecules, such as calcium, nitric oxide and hydrogen peroxide. Furthermore, the -1095 to -416 region of the C4-PEPC promoter in PC plants was demethylated following exposure to drought conditions for 1 h. The demethylation coincided with an increase in C4-PEPC expression. Our data suggest that the demethylation of the C4-PEPC promoter and the phosphorylation catalyzed by PPCK have key roles in conferring drought tolerance to the transgenic rice plants.
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Affiliation(s)
- Xiaolong Liu
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xia Li
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
| | - Chen Zhang
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
| | - Chuanchao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Jiayu Zhou
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Chenggang Ren
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
| | - Jinfei Zhang
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
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Qian B, Li X, Liu X, Wang M. Improved oxidative tolerance in suspension-cultured cells of C4-pepctransgenic rice by H2O2 and Ca(2+) under PEG-6000. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2015; 57:534-549. [PMID: 25231250 DOI: 10.1111/jipb.12283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 09/16/2014] [Indexed: 06/03/2023]
Abstract
To understand the molecular responses of PC (Overexpressing the maize C4-pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC)), to drought stress at cell level, we analyzed changes in the levels of signaling molecules (hydrogen peroxide (H2O2), calcium ion (Ca(2+)), and nitric oxide (NO)) in suspension-cultured PC and wild-type (WT) rice (Oryza sativa L.) cell under drought stress induced by 20% polyethylene glycol 6000 (PEG-6000). Results demonstrated that PC improved drought tolerance by enhancing antioxidant defense, retaining higher relative water content, survival percentages, and dry weight of cells. In addition, PEPC activity in PC under PEG treatment was strengthened by addition of H2O2 inhibitor, dimethylthiourea (DMTU) and NO synthesis inhibitor, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), respectively, while that in PC was weakened by addition of free calcium chelator, ethylene glycol-bis(b-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) + calcium channel outflow inhibitor, ruthenium red (RR) + plasma membrane channel blocker La(NO3)3, but EGTA + RR did not. Results also showed that NO and Ca(2+) was lying downstream of H2O2 in drought-induced signaling. Calcium ion was also involved in the expression of C4-pepc in PC. These results suggested that PC could improve oxidative tolerance in suspension-cultured cells and the acquisition of this tolerance required downregulation of H2O2 and the entry of extracellular Ca(2+) into cells across the plasma membrane for regulation of PEPC activity and C4-pepc expression.
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Affiliation(s)
- Baoyun Qian
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
- Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Xia Li
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
- Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Xiaolong Liu
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
- Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Man Wang
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice Research and Development Center, Nanjing Branch, China National Center for Rice Improvement, Nanjing, 210014, China
- Provincial Key Laboratory of Agrobiology, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
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10
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Qian B, Li X, Liu X, Chen P, Ren C, Dai C. Enhanced drought tolerance in transgenic rice over-expressing of maize C4 phosphoenolpyruvate carboxylase gene via NO and Ca(2+). JOURNAL OF PLANT PHYSIOLOGY 2015; 175:9-20. [PMID: 25460871 DOI: 10.1016/j.jplph.2014.09.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Revised: 07/20/2014] [Accepted: 09/28/2014] [Indexed: 06/04/2023]
Abstract
We determined the effects of endogenous nitric oxide and Ca(2+) on photosynthesis and gene expression in transgenic rice plants (PC) over-expressing the maize C4pepc gene, which encodes phosphoenolpyruvate carboxylase (PEPC) under drought. In this study, seedlings were subjected to PEG 6000 treatments using PC and wild type (WT; Kitaake). The results showed that, compared with WT, PC had higher relative water content (RWC) and net photosynthetic rate (Pn) under drought. During a 2-day re-watering treatment, Pn recovered faster in PC than in WT. Further analyses showed that, under the drought treatment, the amount of endogenous hydrogen peroxide (H2O2) increased in WT mainly via NADPH oxidase. While in PC, the endogenous nitric oxide (NO) content increased via nitrate reductase and nitric oxide synthase on day 2 of the drought treatment and day 1 of the re-watering treatment. After 2 days of drought treatment, PC also showed higher PEPC activity, calcium content, phospholipase D (PLD) activity, C4-pepc and NAC6 transcript levels, and protein kinase activity as compared with PC without treatment. These changes did not occur in WT. Correlation analysis also proved NO associated with these indicators in PC. Based on these results, there was a particular molecular mechanism of drought tolerance in PC. The mechanism is related to the signaling processes via NO and Ca(2+) involving the protein kinase and the transcription factor, resulted in up-regulation of PEPC activity and its gene expression, such as C4pepc. Some genes encode antioxidant system, cu/zn-sod as well, which promote antioxidant system to clear MDA and superoxide anion radical, thereby conferring drought tolerance.
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Affiliation(s)
- Baoyun Qian
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R & D Center, Nanjing Branch, China National Center for Rice Improvement, Provincial Key Laboratory of Agrobiology, Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xia Li
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R & D Center, Nanjing Branch, China National Center for Rice Improvement, Provincial Key Laboratory of Agrobiology, Nanjing 210014, PR China.
| | - Xiaolong Liu
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R & D Center, Nanjing Branch, China National Center for Rice Improvement, Provincial Key Laboratory of Agrobiology, Nanjing 210014, PR China; College of Life Science, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Pingbo Chen
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R & D Center, Nanjing Branch, China National Center for Rice Improvement, Provincial Key Laboratory of Agrobiology, Nanjing 210014, PR China
| | - Chengang Ren
- Institute of Food Crops, Jiangsu Academy of Agricultural Sciences, Jiangsu High Quality Rice R & D Center, Nanjing Branch, China National Center for Rice Improvement, Provincial Key Laboratory of Agrobiology, Nanjing 210014, PR China
| | - Chuanchao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Science, Nanjing Normal University, Nanjing 210023, PR China
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