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Lu F, Liang X, Lu H, Li Q, Chen Q, Zhang P, Li K, Liu G, Yan W, Song J, Duan C, Zhang L. Overproduction of superoxide dismutase and catalase confers cassava resistance to Tetranychus cinnabarinus. Sci Rep 2017; 7:40179. [PMID: 28054665 PMCID: PMC5214258 DOI: 10.1038/srep40179] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 12/05/2016] [Indexed: 12/30/2022] Open
Abstract
To explore the role of protective enzymes in cassava (Manihot esculenta Crantz) resistance to mites, transgenic cassava lines overproducing copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) were used to evaluate and molecularly confirm cassava resistance to Tetranychus cinnabarinus. Laboratory evaluation demonstrated that, compared with the control cultivar TMS60444 (wild type, WT), the survival, reproduction, development and activities of SOD and CAT in T. cinnabarinus feeding on transgenic cassava lines SC2, SC4, and SC11 significantly inhibited. Furthermore, the activities of SOD and CAT in transgenic cassava lines SC2, SC4, and SC11 damaged by T. cinnabarinus significantly increased. These findings were similar to the results in the mite-resistant cassava cultivars. Besides, field evaluation indicated that the transgenic cassava lines SC2, SC4, and SC11 were slightly damaged as the highly mite-resistant control C1115, while the highly mite-susceptible WT was severely damaged by T. cinnabarinus. Laboratory and field evaluation demonstrated that transgenic cassava lines were resistant to T. cinnabarinus, which directly confirmed that the increase in SOD and CAT activities was positively related to cassava resistance to T. cinnabarinus. These results will help in understanding the antioxidant defense responses in the cassava-mite interaction and molecular breeding of mite-resistant cassava for effective pest control.
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Affiliation(s)
- Fuping Lu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Xiao Liang
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Hui Lu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Qian Li
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Qing Chen
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Peng Zhang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - kaimian Li
- Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, China
| | - Guanghua Liu
- Institute of Tropical and Sub-tropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
| | - Wei Yan
- Institute of Tropical and Sub-tropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
| | - Jiming Song
- Institute of Tropical and Sub-tropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
| | - Chunfang Duan
- Institute of Tropical and Sub-tropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
| | - Linhui Zhang
- Institute of Tropical and Sub-tropical Cash Crops, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
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102
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Li X, Fan S, Hu W, Liu G, Wei Y, He C, Shi H. Two Cassava Basic Leucine Zipper (bZIP) Transcription Factors (MebZIP3 and MebZIP5) Confer Disease Resistance against Cassava Bacterial Blight. FRONTIERS IN PLANT SCIENCE 2017; 8:2110. [PMID: 29276527 PMCID: PMC5727076 DOI: 10.3389/fpls.2017.02110] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 11/27/2017] [Indexed: 05/19/2023]
Abstract
Basic domain-leucine zipper (bZIP) transcription factor, one type of conserved gene family, plays an important role in plant development and stress responses. Although 77 MebZIPs have been genome-wide identified in cassava, their in vivo roles remain unknown. In this study, we analyzed the expression pattern and the function of two MebZIPs (MebZIP3 and MebZIP5) in response to pathogen infection. Gene expression analysis indicated that MebZIP3 and MebZIP5 were commonly regulated by flg22, Xanthomonas axonopodis pv. manihotis (Xam), salicylic acid (SA), and hydrogen peroxide (H2O2). Subcellular localization analysis showed that MebZIP3 and MebZIP5 are specifically located in cell nucleus. Through overexpression in tobacco, we found that MebZIP3 and MebZIP5 conferred improved disease resistance against cassava bacterial blight, with more callose depositions. On the contrary, MebZIP3- and MebZIP5-silenced plants by virus-induced gene silencing (VIGS) showed disease sensitive phenotype, lower transcript levels of defense-related genes and less callose depositions. Taken together, this study highlights the positive role of MebZIP3 and MebZIP5 in disease resistance against cassava bacterial blight for further utilization in genetic improvement of cassava disease resistance.
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Affiliation(s)
- Xiaolin Li
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Shuhong Fan
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Wei Hu
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China
| | - Guoyin Liu
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Yunxie Wei
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
| | - Chaozu He
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
- *Correspondence: Haitao Shi, Chaozu He,
| | - Haitao Shi
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources and College of Biology, Institute of Tropical Agriculture and Forestry, Hainan University, Haikou, China
- *Correspondence: Haitao Shi, Chaozu He,
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103
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Feller U. Drought stress and carbon assimilation in a warming climate: Reversible and irreversible impacts. JOURNAL OF PLANT PHYSIOLOGY 2016; 203:84-94. [PMID: 27083537 DOI: 10.1016/j.jplph.2016.04.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/01/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
Global change is characterized by increased CO2 concentration in the atmosphere, increasing average temperature and more frequent extreme events including drought periods, heat waves and flooding. Especially the impacts of drought and of elevated temperature on carbon assimilation are considered in this review. Effects of extreme events on the subcellular level as well as on the whole plant level may be reversible, partially reversible or irreversible. The photosynthetically active biomass depends on the number and the size of mature leaves and the photosynthetic activity in this biomass during stress and subsequent recovery phases. The total area of active leaves is determined by leaf expansion and senescence, while net photosynthesis per leaf area is primarily influenced by stomatal opening (stomatal conductance), mesophyll conductance, activity of the photosynthetic apparatus (light absorption and electron transport, activity of the Calvin cycle) and CO2 release by decarboxylation reactions (photorespiration, dark respiration). Water status, stomatal opening and leaf temperature represent a "magic triangle" of three strongly interacting parameters. The response of stomata to altered environmental conditions is important for stomatal limitations. Rubisco protein is quite thermotolerant, but the enzyme becomes at elevated temperature more rapidly inactivated (decarbamylation, reversible effect) and must be reactivated by Rubisco activase (carbamylation of a lysine residue). Rubisco activase is present under two forms (encoded by separate genes or products of alternative splicing of the pre-mRNA from one gene) and is very thermosensitive. Rubisco activase was identified as a key protein for photosynthesis at elevated temperature (non-stomatal limitation). During a moderate heat stress Rubisco activase is reversibly inactivated, but during a more severe stress (higher temperature and/or longer exposure) the protein is irreversibly inactivated, insolubilized and finally degraded. On the level of the leaf, this loss of photosynthetic activity may still be reversible when new Rubisco activase is produced by protein synthesis. Rubisco activase as well as enzymes involved in the detoxification of reactive oxygen species or in osmoregulation are considered as important targets for breeding crop plants which are still productive under drought and/or at elevated leaf temperature in a changing climate.
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Affiliation(s)
- Urs Feller
- Institute of Plant Sciences and Oeschger Centre for Climate Change Research (OCCR), University of Bern, Altenbergrain 21, CH-3013 Bern, Switzerland.
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104
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Cao L, Yu Y, DuanMu H, Chen C, Duan X, Zhu P, Chen R, Li Q, Zhu Y, Ding X. A novel Glycine soja homeodomain-leucine zipper (HD-Zip) I gene, Gshdz4, positively regulates bicarbonate tolerance and responds to osmotic stress in Arabidopsis. BMC PLANT BIOLOGY 2016; 16:184. [PMID: 27553065 PMCID: PMC4995822 DOI: 10.1186/s12870-016-0872-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 08/15/2016] [Indexed: 05/24/2023]
Abstract
BACKGROUND Wild soybean (Glycine soja) is a highly adaptive plant species which can grow well in saline-alkaline soils. In soybean genome, there exist about 140 HD-Zip (Homeodomain-leucine Zipper) genes. HD-Zip transcription factor family is one of the largest plant specific superfamilies and plays important roles in response to abiotic stresses. Although HD-Zip transcription factors have been broadly reported to be involved in plant resistance to abiotic stresses like salt and drought, their roles in response to bicarbonate stress is largely unknown. RESULTS From our previous transcriptome profile analysis of wild soybean treated by 50 mM NaHCO3, we identified an HD-Zip gene (Gshdz4) which showed high response to the alkaline stress. Our result of qRT-PCR showed that the expression of Gshdz4 was induced by alkaline stress (NaHCO3) in both leaves and roots of wild soybean. Overexpression of Gshdz4 in Arabidopsis resulted in enhanced tolerance to NaHCO3 and KHCO3 during the process of plant growth and development. However, the growths of transgenic and WT plants were not significantly different on the medium with high pH adjusted by KOH, implicating Gshdz4 is only responsible for resisting HCO3 (-) but not high pH. The transgenic plants had less MDA contents but higher POD activities and chlorophyll contents than the WT plants. Moreover, the transcript levels of stress-related genes, such as NADP-ME, H (+) -Ppase, RD29B and KIN1 were increased with greater extent in the transgenic plants than the wild plants. On the contrary, Gshdz4 overexpression lines were much sensitive to osmotic stress at seed germination and stocking stages compared to the wild plants. CONCLUSIONS We revealed that the important and special roles of Gshdz4 in enhancing bicarbonate tolerance and responding to osmotic stress. It is the first time to elucidate these novel functions of HD-ZIP transcription factors. All the evidences broaden our understanding of functions of HD-Zip family and provide clues for uncovering the mechanisms of high tolerance of wild soybean to saline-alkaline stresses.
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Affiliation(s)
- Lei Cao
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Yang Yu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Huizi DuanMu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Chao Chen
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Xiangbo Duan
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Pinghui Zhu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Ranran Chen
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Qiang Li
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Yanming Zhu
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
| | - Xiaodong Ding
- Key Laboratory of Agricultural Biological Functional Genes, Northeast Agricultural University, Harbin, 150030 China
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105
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Ding Z, Zhang Y, Xiao Y, Liu F, Wang M, Zhu X, Liu P, Sun Q, Wang W, Peng M, Brutnell T, Li P. Transcriptome response of cassava leaves under natural shade. Sci Rep 2016; 6:31673. [PMID: 27539510 PMCID: PMC4990974 DOI: 10.1038/srep31673] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 07/21/2016] [Indexed: 11/19/2022] Open
Abstract
Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and genes related to photosynthesis and carbohydrates metabolism were highly expressed in mature leaves. Compared with the control, shade significantly induced the expression of genes involved in light reaction of photosynthesis, light signaling and DNA synthesis/chromatin structure; however, the genes related to anthocyanins biosynthesis, heat shock, calvin cycle, glycolysis, TCA cycle, mitochondrial electron transport, and starch and sucrose metabolisms were dramatically depressed. Moreover, the shade also influenced the expression of hormone-related genes and transcriptional factors. The findings would improve our understanding of molecular mechanisms of shade response, and shed light on pathways associated with shade-avoidance syndrome for cassava improvement.
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Affiliation(s)
- Zehong Ding
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, The Institute of Tropical Bioscience and Biotechnology (ITBB), Chinese Academy of Tropical Agricultural Sciences (CATAS), Haikou, Hainan 571101, China
| | - Yang Zhang
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, Nebraska 68583, USA.,Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska 68583, USA
| | - Yi Xiao
- CAS-Key laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, CAS, Shanghai 200031, China
| | - Fangfang Liu
- Department of Statistics, Iowa State University, Ames, Iowa 50011, USA
| | - Minghui Wang
- Computational Biology Service Unit, Life Sciences Core Laboratories Center, Cornell University, Ithaca, New York 14850, USA
| | - Xinguang Zhu
- CAS-Key laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, CAS, Shanghai 200031, China
| | - Peng Liu
- Department of Statistics, Iowa State University, Ames, Iowa 50011, USA
| | - Qi Sun
- Computational Biology Service Unit, Life Sciences Core Laboratories Center, Cornell University, Ithaca, New York 14850, USA
| | - Wenquan Wang
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, The Institute of Tropical Bioscience and Biotechnology (ITBB), Chinese Academy of Tropical Agricultural Sciences (CATAS), Haikou, Hainan 571101, China
| | - Ming Peng
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, The Institute of Tropical Bioscience and Biotechnology (ITBB), Chinese Academy of Tropical Agricultural Sciences (CATAS), Haikou, Hainan 571101, China
| | - Tom Brutnell
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
| | - Pinghua Li
- State Key Laboratory of Crop Biology, College of Agronomic Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, China
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106
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Ma Q, Zhang T, Zhang P, Wang ZY. Melatonin attenuates postharvest physiological deterioration of cassava storage roots. J Pineal Res 2016; 60:424-34. [PMID: 26989849 DOI: 10.1111/jpi.12325] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 03/11/2016] [Indexed: 01/06/2023]
Abstract
Melatonin reportedly increases abiotic and biotic stress tolerance in plants, but information on its in vivo effects during postharvest physiological deterioration (PPD) in cassava is limited. In this study, we investigated the effect of melatonin in regulating cassava PPD. Treatment with 500 mg/L melatonin significantly delayed cassava PPD and reduced the accumulation of hydrogen peroxide (H2O2) while increasing the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR), but not ascorbate peroxidase (APX). Transcript analysis further showed that expression of copper/zinc SOD (MeCu/ZnSOD), MeCAT1, glutathione peroxidase (MeGPX), peroxidase 3 (MePX3), and glutathione S-transferases (MeGST) was higher in cassava roots sliced treated with 500 mg/L melatonin than in those not exposed to exogenous melatonin. These data demonstrate that melatonin delays cassava PPD by directly or indirectly maintaining homoeostasis of cellular reactive oxygen species (ROS). We also found that accumulation of endogenous melatonin and the transcript levels of melatonin biosynthesis genes changed dynamically during the PPD process. This finding suggested that endogenous melatonin acts as a signal modulator for maintaining cassava PPD progression and that manipulation of melatonin biosynthesis genes through genetic engineering might prevent cassava root deterioration.
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Affiliation(s)
- Qiuxiang Ma
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Ting Zhang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Peng Zhang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhen-Yu Wang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou, China
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107
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Fu L, Ding Z, Han B, Hu W, Li Y, Zhang J. Physiological Investigation and Transcriptome Analysis of Polyethylene Glycol (PEG)-Induced Dehydration Stress in Cassava. Int J Mol Sci 2016; 17:283. [PMID: 26927071 PMCID: PMC4813147 DOI: 10.3390/ijms17030283] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 01/28/2016] [Accepted: 02/15/2016] [Indexed: 12/02/2022] Open
Abstract
Cassava is an important tropical and sub-tropical root crop that is adapted to drought environment. However, severe drought stress significantly influences biomass accumulation and starchy root production. The mechanism underlying drought-tolerance remains obscure in cassava. In this study, changes of physiological characters and gene transcriptome profiles were investigated under dehydration stress simulated by polyethylene glycol (PEG) treatments. Five traits, including peroxidase (POD) activity, proline content, malondialdehyde (MDA), soluble sugar and soluble protein, were all dramatically induced in response to PEG treatment. RNA-seq analysis revealed a gradient decrease of differentially expressed (DE) gene number in tissues from bottom to top of a plant, suggesting that cassava root has a quicker response and more induced/depressed DE genes than leaves in response to drought. Overall, dynamic changes of gene expression profiles in cassava root and leaves were uncovered: genes related to glycolysis, abscisic acid and ethylene biosynthesis, lipid metabolism, protein degradation, and second metabolism of flavonoids were significantly induced, while genes associated with cell cycle/organization, cell wall synthesis and degradation, DNA synthesis and chromatin structure, protein synthesis, light reaction of photosynthesis, gibberelin pathways and abiotic stress were greatly depressed. Finally, novel pathways in ABA-dependent and ABA-independent regulatory networks underlying PEG-induced dehydration response in cassava were detected, and the RNA-Seq results of a subset of fifteen genes were confirmed by real-time PCR. The findings will improve our understanding of the mechanism related to dehydration stress-tolerance in cassava and will provide useful candidate genes for breeding of cassava varieties better adapted to drought environment.
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Affiliation(s)
- Lili Fu
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
| | - Zehong Ding
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
| | - Bingying Han
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
| | - Wei Hu
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
| | - Yajun Li
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
| | - Jiaming Zhang
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road 4, Haikou 571101, China.
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108
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Participatory appraisal of preferred traits, production constraints and postharvest challenges for cassava farmers in Rwanda. Food Secur 2016. [DOI: 10.1007/s12571-016-0556-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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109
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Liao W, Wang G, Li Y, Wang B, Zhang P, Peng M. Reactive oxygen species regulate leaf pulvinus abscission zone cell separation in response to water-deficit stress in cassava. Sci Rep 2016; 6:21542. [PMID: 26899473 PMCID: PMC4761936 DOI: 10.1038/srep21542] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/26/2016] [Indexed: 12/26/2022] Open
Abstract
Cassava (Manihot esculenta Crantz) plant resists water-deficit stress by shedding leaves leading to adaptive water-deficit condition. Transcriptomic, physiological, cellular, molecular, metabolic, and transgenic methods were used to study the mechanism of cassava abscission zone (AZ) cell separation under water-deficit stress. Microscopic observation indicated that AZ cell separation initiated at the later stages during water-deficit stress. Transcriptome profiling of AZ suggested that differential expression genes of AZ under stress mainly participate in reactive oxygen species (ROS) pathway. The key genes involved in hydrogen peroxide biosynthesis and metabolism showed significantly higher expression levels in AZ than non-separating tissues adjacent to the AZ under stress. Significantly higher levels of hydrogen peroxide correlated with hydrogen peroxide biosynthesis related genes and AZ cell separation was detected by microscopic observation, colorimetric detection and GC-MS analyses under stress. Co-overexpression of the ROS-scavenging proteins SOD and CAT1 in cassava decreased the levels of hydrogen peroxide in AZ under water-deficit stress. The cell separation of the pulvinus AZ also delayed in co-overexpression of the ROS-scavenging proteins SOD and CAT1 plants both in vitro and at the plant level. Together, the results indicated that ROS play an important regulatory role in the process of cassava leaf abscission under water-deficit stress.
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Affiliation(s)
- Wenbin Liao
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Gan Wang
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Yayun Li
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Bin Wang
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Peng Zhang
- National Key Laboratory of Plant Molecular Genetics, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai 200032, China
| | - Ming Peng
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
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110
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Hu W, Kong H, Guo Y, Zhang Y, Ding Z, Tie W, Yan Y, Huang Q, Peng M, Shi H, Guo A. Comparative Physiological and Transcriptomic Analyses Reveal the Actions of Melatonin in the Delay of Postharvest Physiological Deterioration of Cassava. FRONTIERS IN PLANT SCIENCE 2016; 7:736. [PMID: 27303428 PMCID: PMC4882330 DOI: 10.3389/fpls.2016.00736] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Accepted: 05/12/2016] [Indexed: 05/18/2023]
Abstract
Melatonin plays important roles in various aspects of biological processes. However, it is less known on the effects and mechanism of melatonin on the postharvest physiological deterioration (PPD) process of cassava, which largely restricts the potential of cassava as a food and industrial crop. In this study, we found that exogenous application of melatonin significantly delayed PPD of cassava tuberous roots by reducing H2O2 content and improving activities of catalase and peroxidase. Moreover, 3425 differentially expressed genes by melatonin during the PPD process were identified by transcriptomic analysis. Several pathways were markedly affected by melatonin treatments, including metabolic-, ion homeostasis-, and enzyme activity-related processes. Further detailed analysis revealed that melatonin acted through activation of ROS-scavenging and ROS signal transduction pathways, including antioxidant enzymes, calcium signaling, MAPK cascades, and transcription factors at early stages. Notably, the starch degradation pathway was also activated at early stages, whereas it was repressed by melatonin at middle and late stages, thereby indicating its regulatory role in starch metabolism during PPD. Taken together, this study yields new insights into the effect and underlying mechanism of melatonin on the delay of PPD and provides a good strategy for extending shelf life and improvement of cassava tuberous roots.
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Affiliation(s)
- Wei Hu
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Hua Kong
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Yunling Guo
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Yuliang Zhang
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Zehong Ding
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Weiwei Tie
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Yan Yan
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Qixing Huang
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Ming Peng
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Haitao Shi
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan UniversityHaikou, China
- *Correspondence: Haitao Shi, ; Anping Guo,
| | - Anping Guo
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
- *Correspondence: Haitao Shi, ; Anping Guo,
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111
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Kerchev P, De Smet B, Waszczak C, Messens J, Van Breusegem F. Redox Strategies for Crop Improvement. Antioxid Redox Signal 2015; 23:1186-205. [PMID: 26062101 DOI: 10.1089/ars.2014.6033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
SIGNIFICANCE Recently, the agro-biotech industry has been driven by overcoming the limitations imposed by fluctuating environmental stress conditions on crop productivity. A common theme among (a)biotic stresses is the perturbation of the redox homeostasis. RECENT ADVANCES As a strategy to engineer stress-tolerant crops, many approaches have been centered on restricting the negative impact of reactive oxygen species (ROS) accumulation. CRITICAL ISSUES In this study, we discuss the scientific background of the existing redox-based strategies to improve crop performance and quality. In this respect, a special focus goes to summarizing the current patent landscape because this aspect is very often ignored, despite constituting the forefront of applied research. FUTURE DIRECTIONS The current increased understanding of ROS acting as signaling molecules has opened new avenues to exploit redox biology for crop improvement required for sustainable food security.
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Affiliation(s)
- Pavel Kerchev
- 1 Department of Plant Systems Biology , VIB, Ghent, Belgium .,2 Department of Plant Biotechnology and Bioinformatics, Ghent University , Ghent, Belgium
| | - Barbara De Smet
- 1 Department of Plant Systems Biology , VIB, Ghent, Belgium .,2 Department of Plant Biotechnology and Bioinformatics, Ghent University , Ghent, Belgium .,3 Structural Biology Research Center , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussel, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussel, Belgium
| | - Cezary Waszczak
- 1 Department of Plant Systems Biology , VIB, Ghent, Belgium .,2 Department of Plant Biotechnology and Bioinformatics, Ghent University , Ghent, Belgium .,3 Structural Biology Research Center , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussel, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussel, Belgium
| | - Joris Messens
- 3 Structural Biology Research Center , VIB, Brussels, Belgium .,4 Brussels Center for Redox Biology , Brussel, Belgium .,5 Structural Biology Brussels, Vrije Universiteit Brussel , Brussel, Belgium
| | - Frank Van Breusegem
- 1 Department of Plant Systems Biology , VIB, Ghent, Belgium .,2 Department of Plant Biotechnology and Bioinformatics, Ghent University , Ghent, Belgium
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112
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Ma C, Burd S, Lers A. miR408 is involved in abiotic stress responses in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2015; 84:169-87. [PMID: 26312768 DOI: 10.1111/tpj.12999] [Citation(s) in RCA: 160] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/08/2015] [Accepted: 08/13/2015] [Indexed: 05/22/2023]
Abstract
MicroRNAs (miRNAs) are small RNAs that regulate the expression of target genes post-transcriptionally; they are known to play major roles in development and responses to abiotic stress. miR408 is a highly conserved miRNA in plants that responds to the availability of copper and targets genes encoding copper-containing proteins. It was recently recognized to be an important component of the HY5-SPL7 gene network that mediates a coordinated response to light and copper, illustrating its central role in the response of plants to the environment. Expression of miR408 is significantly affected by a variety of developmental and environmental conditions; however, its biological function is unknown. Involvement of miR408 in the abiotic stress response was investigated in Arabidopsis. Expression of miR408, as well as its target genes, was investigated in response to salinity, cold, oxidative stress, drought and osmotic stress. Analyses of transgenic plants with modulated miR408 expression revealed that higher miR408 expression leads to improved tolerance to salinity, cold and oxidative stress, but enhanced sensitivity to drought and osmotic stress. Cellular antioxidant capacity was enhanced in plants with elevated miR408 expression, as manifested by reduced levels of reactive oxygen species and induced expression of genes associated with antioxidative functions, including Cu/Zn superoxide dismutases (CSD1 and CSD2) and glutathione-S-transferase (GST-U25), as well as auxiliary genes: the copper chaperone CCS1 and the redox stress-associated gene SAP12. Overall, the results demonstrate significant involvement of miR408 in abiotic stress responses, emphasizing the central function of miR408 in plant survival.
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Affiliation(s)
- Chao Ma
- Department of Plant Science, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, China
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
| | - Shaul Burd
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
| | - Amnon Lers
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
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113
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Hu W, Hou X, Xia Z, Yan Y, Wei Y, Wang L, Zou M, Lu C, Wang W, Peng M. Genome-wide survey and expression analysis of the calcium-dependent protein kinase gene family in cassava. Mol Genet Genomics 2015; 291:241-53. [DOI: 10.1007/s00438-015-1103-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/05/2015] [Indexed: 12/25/2022]
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114
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Yan Z, Hossain MS, Arikit S, Valdés-López O, Zhai J, Wang J, Libault M, Ji T, Qiu L, Meyers BC, Stacey G. Identification of microRNAs and their mRNA targets during soybean nodule development: functional analysis of the role of miR393j-3p in soybean nodulation. THE NEW PHYTOLOGIST 2015; 207:748-59. [PMID: 25783944 DOI: 10.1111/nph.13365] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 02/09/2015] [Indexed: 05/25/2023]
Abstract
Plant microRNAs (miRNAs) play important regulatory roles in a number of developmental processes. The present work investigated the roles of miRNAs during nodule development in the crop legume soybean (Glycine max). Fifteen soybean small RNA libraries were sequenced from different stages of nodule development, including young nodules, mature nodules and senescent nodules. In order to identify the regulatory targets of the miRNAs, five parallel analysis of RNA ends (PARE) libraries were also sequenced from the same stages of nodule development. Sequencing identified 284 miRNAs, including 178 novel soybean miRNAs. Analysis of miRNA abundance identified 139 miRNAs whose expression was significantly regulated during nodule development, including 12 miRNAs whose expression changed > 10-fold. Analysis of the PARE libraries identified 533 miRNA targets, including three nodulation-related genes and eight nodule-specific genes. miR393j-3p was selected for detailed analysis as its expression was significantly regulated during nodule formation, and it targeted a nodulin gene, Early Nodulin 93 (ENOD93). Strong, ectopic expression of miR393j-3p, as well as RNAi silencing of ENOD93 expression, significantly reduced nodule formation. The data indicate that miR393j-3p regulation of ENOD93 mRNA abundance is a key control point for soybean nodule formation.
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Affiliation(s)
- Zhe Yan
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Md Shakhawat Hossain
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Siwaret Arikit
- Department of Plant and Soil Sciences and Delaware Biotechnology Institute, University of Delaware, Newark, DE, 19711, USA
| | - Oswaldo Valdés-López
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Jixian Zhai
- Department of Plant and Soil Sciences and Delaware Biotechnology Institute, University of Delaware, Newark, DE, 19711, USA
| | - Jun Wang
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
- National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Marc Libault
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Tieming Ji
- Department of Statistics, University of Missouri, 209D Middlebush Hall, Columbia, MO, 65211, USA
| | - Lijuan Qiu
- National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Blake C Meyers
- Department of Plant and Soil Sciences and Delaware Biotechnology Institute, University of Delaware, Newark, DE, 19711, USA
| | - Gary Stacey
- Divisions of Plant Science and Biochemistry, National Center for Soybean Biotechnology, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
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115
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Li C, Shi L, Chen D, Ren A, Gao T, Zhao M. Functional analysis of the role of glutathione peroxidase (GPx) in the ROS signaling pathway, hyphal branching and the regulation of ganoderic acid biosynthesis in Ganoderma lucidum. Fungal Genet Biol 2015. [PMID: 26216672 DOI: 10.1016/j.fgb.2015.07.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ganoderma lucidum, a hallmark of traditional Chinese medicine, has been widely used as a pharmacologically active compound. Although numerous research studies have focused on the pharmacological mechanism, fewer studies have explored the basic biological features of this species, restricting the further development and application of this important mushroom. Because of the ability of this mushroom to reduce and detoxify the compounds produced by various metabolic pathways, glutathione peroxidase (GPx) is one of the most important antioxidant enzymes with respect to ROS. Although studies in both animals and plants have suggested many important physiological functions of GPx, there are few systematic research studies concerning the role of this enzyme in fungi, particularly in large basidiomycetes. In the present study, we cloned the GPx gene and created GPx-silenced strains by the down-regulation of GPx gene expression using RNA interference. The results indicated an essential role for GPx in controlling the intracellular H2O2 content, hyphal branching, antioxidant stress tolerance, cytosolic Ca(2+) content and ganoderic acid biosynthesis. Further mechanistic investigation revealed that GPx is regulated by intracellular H2O2 levels and suggested that crosstalk occurs between GPx and intracellular H2O2. Moreover, evidence was obtained indicating that GPx regulation of hyphal branching via ROS might occur independently of the cytosolic Ca(2+) content. Further mechanistic investigation also revealed that the effects of GPx on ganoderic acid synthesis via ROS are regulated by the cytosolic Ca(2+) content. Taken together, these findings indicate that ROS have a complex influence on growth, development and secondary metabolism in fungi and that GPx serves an important function. The present study provides an excellent framework to identify GPx functions and highlights a role for this enzyme in ROS regulation.
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Affiliation(s)
- Chenyang Li
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China
| | - Liang Shi
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China
| | - Dongdong Chen
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China
| | - Ang Ren
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China
| | - Tan Gao
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China
| | - Mingwen Zhao
- College of Life Sciences, Nanjing Agricultural University, Key Laboratory of Microbiological Engineering of Agricultural Environment, Ministry of Agriculture, Nanjing 210095, Jiangsu, People's Republic of China.
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116
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Easwar Rao D, Chaitanya K. Varietal Differences in the Antioxidative Properties of Soybean [Glycine Max
(L.) Merr.] Seeds. J Food Biochem 2015. [DOI: 10.1111/jfbc.12136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- D. Easwar Rao
- Department of Biotechnology; GITAM Institute of Technology; GITAM University; Visakhapatnam 530045 India
| | - K.V. Chaitanya
- Department of Biotechnology; GITAM Institute of Technology; GITAM University; Visakhapatnam 530045 India
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Functional Validation of Phragmites communis Glutathione Reductase (PhaGR) as an Essential Enzyme in Salt Tolerance. Appl Biochem Biotechnol 2015; 175:3418-30. [DOI: 10.1007/s12010-015-1514-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 01/21/2015] [Indexed: 11/26/2022]
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Abstract
Genetic transformation of plants is an indispensable technique used for fundamental research and crop improvement. Recent advances in cassava (Manihot esculenta Crantz) transformation have facilitated the effective generation of stably transformed cassava plants with favorable traits. Agrobacterium-mediated transformation of friable, embryogenic callus has evolved to become the most widely used approach and has been adopted by research laboratories in Africa. This procedure utilizes axillary meristem tissue (buds) to produce primary and secondary somatic embryos and subsequently friable, embryogenic callus. Agrobacterium harboring a binary expression cassette is used to transform this tissue, which is regenerated via cotyledons and shoot organogenesis to produce rooted in vitro plantlets. This chapter details each step of the procedure using the model cultivar 60444 and provides supplementary notes to successfully produce transgenic cassava.
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119
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Ma Q, Zhou W, Zhang P. Transition from somatic embryo to friable embryogenic callus in cassava: dynamic changes in cellular structure, physiological status, and gene expression profiles. FRONTIERS IN PLANT SCIENCE 2015; 6:824. [PMID: 26500668 PMCID: PMC4594424 DOI: 10.3389/fpls.2015.00824] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/22/2015] [Indexed: 05/20/2023]
Abstract
Friable embryogenic callus (FEC) is considered as the most suitable material for efficient genetic transformation of cassava. Heavy genotype dependence of FEC induction and amenability to somaclonal variation limits the production and maintenance of reliable FEC. Identifying key elements involved in biological processes from somatic embryos (SEs) to FEC at different stages provides critical insights for FEC improvement. Cytological observation showed a dramatic change of subcellular structures among SEs, fresh FEC (FFEC), and old FEC (OFEC). Decrease of sucrose and increase of fructose and glucose were detected in OFEC. A total of 6871 differentially expressed genes (DEGs) were identified from SEs, FFEC, and OFEC by RNA-seq. Analysis of the DEGs showed that FEC induction was accompanied by the process of dedifferentiation, whereas the epigenetics modification occurred during the continuous subculturing process. The cell structure was reconstructed, mainly including the GO terms of "cell periphery" and "external encapsulating structure"; in parallel, the internal mechanisms changed correspondingly, including the biological process of glycolysis and metabolisms of alanine, aspartate, and glutamate. The significant reduction of genomic DNA methylation in OFEC indicated altered gene expression via chromatin modification. These results indicate that the induction and long-term subculture of FEC is a complicated biological process involving changes of genome modification, gene expression, and subcellular reconstruction. The findings will be useful for improving FEC induction and maintenance from farmer-preferred cassava cultivars recalcitrant to genetic transformation, hence improving cassava through genetic engineering.
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Affiliation(s)
| | | | - Peng Zhang
- *Correspondence: Peng Zhang, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China
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120
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Hu W, Xia Z, Yan Y, Ding Z, Tie W, Wang L, Zou M, Wei Y, Lu C, Hou X, Wang W, Peng M. Genome-wide gene phylogeny of CIPK family in cassava and expression analysis of partial drought-induced genes. FRONTIERS IN PLANT SCIENCE 2015; 6:914. [PMID: 26579161 PMCID: PMC4626571 DOI: 10.3389/fpls.2015.00914] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 10/12/2015] [Indexed: 05/19/2023]
Abstract
Cassava is an important food and potential biofuel crop that is tolerant to multiple abiotic stressors. The mechanisms underlying these tolerances are currently less known. CBL-interacting protein kinases (CIPKs) have been shown to play crucial roles in plant developmental processes, hormone signaling transduction, and in the response to abiotic stress. However, no data is currently available about the CPK family in cassava. In this study, a total of 25 CIPK genes were identified from cassava genome based on our previous genome sequencing data. Phylogenetic analysis suggested that 25 MeCIPKs could be classified into four subfamilies, which was supported by exon-intron organizations and the architectures of conserved protein motifs. Transcriptomic analysis of a wild subspecies and two cultivated varieties showed that most MeCIPKs had different expression patterns between wild subspecies and cultivatars in different tissues or in response to drought stress. Some orthologous genes involved in CIPK interaction networks were identified between Arabidopsis and cassava. The interaction networks and co-expression patterns of these orthologous genes revealed that the crucial pathways controlled by CIPK networks may be involved in the differential response to drought stress in different accessions of cassava. Nine MeCIPK genes were selected to investigate their transcriptional response to various stimuli and the results showed the comprehensive response of the tested MeCIPK genes to osmotic, salt, cold, oxidative stressors, and ABA signaling. The identification and expression analysis of CIPK family suggested that CIPK genes are important components of development and multiple signal transduction pathways in cassava. The findings of this study will help lay a foundation for the functional characterization of the CIPK gene family and provide an improved understanding of abiotic stress responses and signaling transduction in cassava.
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Affiliation(s)
- Wei Hu
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
- *Correspondence: Wei Hu
| | - Zhiqiang Xia
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Yan Yan
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Zehong Ding
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Weiwei Tie
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Lianzhe Wang
- College of Life Science and Engineering, Henan University of Urban ConstructionPingdingshan, China
| | - Meiling Zou
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Yunxie Wei
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Cheng Lu
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Xiaowan Hou
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
| | - Wenquan Wang
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
- Wenquan Wang
| | - Ming Peng
- Key Laboratory of Biology and Genetic Resources of Tropical Crops, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural SciencesHaikou, China
- Ming Peng
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Pruthvi V, Narasimhan R, Nataraja KN. Simultaneous expression of abiotic stress responsive transcription factors, AtDREB2A, AtHB7 and AtABF3 improves salinity and drought tolerance in peanut (Arachis hypogaea L.). PLoS One 2014; 9:e111152. [PMID: 25474740 PMCID: PMC4256372 DOI: 10.1371/journal.pone.0111152] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 09/29/2014] [Indexed: 12/25/2022] Open
Abstract
Drought, salinity and extreme temperatures are the most common abiotic stresses, adversely affecting plant growth and productivity. Exposure of plants to stress activates stress signalling pathways that induce biochemical and physiological changes essential for stress acclimation. Stress tolerance is governed by multiple traits, and importance of a few traits in imparting tolerance has been demonstrated. Under drought, traits linked to water mining and water conservation, water use efficiency and cellular tolerance (CT) to desiccation are considered to be relevant. In this study, an attempt has been made to improve CT in drought hardy crop, peanut (Arachis hypogaea L., cv. TMV2) by co-expressing stress-responsive transcription factors (TFs), AtDREB2A, AtHB7 and AtABF3, associated with downstream gene expression. Transgenic plants simultaneously expressing these TFs showed increased tolerance to drought, salinity and oxidative stresses compared to wild type, with an increase in total plant biomass. The transgenic plants exhibited improved membrane and chlorophyll stability due to enhanced reactive oxygen species scavenging and osmotic adjustment by proline synthesis under stress. The improvement in stress tolerance in transgenic lines were associated with induced expression of various CT related genes like AhGlutaredoxin, AhAldehyde reductase, AhSerine threonine kinase like protein, AhRbx1, AhProline amino peptidase, AhHSP70, AhDIP and AhLea4. Taken together the results indicate that co-expression of stress responsive TFs can activate multiple CT pathways, and this strategy can be employed to improve abiotic stress tolerance in crop plants.
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Affiliation(s)
- Vittal Pruthvi
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
| | - Rama Narasimhan
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
| | - Karaba N. Nataraja
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
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MA YONGJIANG, TIAN MIAO, LIU PIN, WANG ZILING, GUAN YUAN, LIU YAN, WANG YUTANG, SHAN ZHAOLIANG. Piperine effectively protects primary cultured atrial myocytes from oxidative damage in the infant rabbit model. Mol Med Rep 2014; 10:2627-32. [DOI: 10.3892/mmr.2014.2554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 05/21/2014] [Indexed: 11/06/2022] Open
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Xu J, Yang J, Duan X, Jiang Y, Zhang P. Increased expression of native cytosolic Cu/Zn superoxide dismutase and ascorbate peroxidase improves tolerance to oxidative and chilling stresses in cassava (Manihot esculenta Crantz). BMC PLANT BIOLOGY 2014; 14:208. [PMID: 25091029 PMCID: PMC4236755 DOI: 10.1186/s12870-014-0208-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/22/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Cassava (Manihot esculenta Crantz) is a tropical root crop, and is therefore, extremely sensitive to low temperature; its antioxidative response is pivotal for its survival under stress. Timely turnover of reactive oxygen species (ROS) in plant cells generated by chilling-induced oxidative damages, and scavenging can be achieved by non-enzymatic and enzymatic reactions in order to maintain ROS homeostasis. RESULTS Transgenic cassava plants that co-express cytosolic superoxide dismutase (SOD), MeCu/ZnSOD, and ascorbate peroxidase (APX), MeAPX2, were produced and tested for tolerance against oxidative and chilling stresses. The up-regulation of MeCu/ZnSOD and MeAPX2 expression was confirmed by the quantitative reverse transcriptase-polymerase chain reaction, and enzymatic activity analyses in the leaves of transgenic cassava plant lines with a single-transgene integration site. Upon exposure to ROS-generating agents, 100 μM ROS-generating reagent methyl viologen and 0.5 M H₂O₂, higher levels of enzymatic activities of SOD and APX were detected in transgenic plants than the wild type. Consequently, the oxidative stress parameters, such as lipid peroxidation, chlorophyll degradation and H₂O₂ synthesis, were lower in the transgenic lines than the wild type. Tolerance to chilling stress at 4°C for 2 d was greater in transgenic cassava, as observed by the higher levels of SOD, catalase, and ascorbate-glutathione cycle enzymes (e.g., APX, monodehydroascorbate reductase, dehydroascorbate reducatase and glutathione reductase) and lower levels of malondialdehyde content. CONCLUSIONS These results suggest that the expression of native cytosolic SOD and APX simultaneously activated the antioxidative defense mechanisms via cyclic ROS scavenging, thereby improving its tolerance to cold stress.
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Affiliation(s)
- Jia Xu
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai Chenshan Botanical Garden, 3888 Chenhua Road, Shanghai 201602, China
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Jun Yang
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai Chenshan Botanical Garden, 3888 Chenhua Road, Shanghai 201602, China
| | - Xiaoguang Duan
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yueming Jiang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Peng Zhang
- Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai Chenshan Botanical Garden, 3888 Chenhua Road, Shanghai 201602, China
- National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research (Shanghai), Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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Vanderschuren H, Nyaboga E, Poon JS, Baerenfaller K, Grossmann J, Hirsch-Hoffmann M, Kirchgessner N, Nanni P, Gruissem W. Large-Scale Proteomics of the Cassava Storage Root and Identification of a Target Gene to Reduce Postharvest Deterioration. THE PLANT CELL 2014; 26:1913-1924. [PMID: 24876255 PMCID: PMC4079358 DOI: 10.1105/tpc.114.123927] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 04/07/2014] [Accepted: 05/02/2014] [Indexed: 05/02/2023]
Abstract
Cassava (Manihot esculenta) is the most important root crop in the tropics, but rapid postharvest physiological deterioration (PPD) of the root is a major constraint to commercial cassava production. We established a reliable method for image-based PPD symptom quantification and used label-free quantitative proteomics to generate an extensive cassava root and PPD proteome. Over 2600 unique proteins were identified in the cassava root, and nearly 300 proteins showed significant abundance regulation during PPD. We identified protein abundance modulation in pathways associated with oxidative stress, phenylpropanoid biosynthesis (including scopoletin), the glutathione cycle, fatty acid α-oxidation, folate transformation, and the sulfate reduction II pathway. Increasing protein abundances and enzymatic activities of glutathione-associated enzymes, including glutathione reductases, glutaredoxins, and glutathione S-transferases, indicated a key role for ascorbate/glutathione cycles. Based on combined proteomics data, enzymatic activities, and lipid peroxidation assays, we identified glutathione peroxidase as a candidate for reducing PPD. Transgenic cassava overexpressing a cytosolic glutathione peroxidase in storage roots showed delayed PPD and reduced lipid peroxidation as well as decreased H2O2 accumulation. Quantitative proteomics data from ethene and phenylpropanoid pathways indicate additional gene candidates to further delay PPD. Cassava root proteomics data are available at www.pep2pro.ethz.ch for easy access and comparison with other proteomics data.
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Affiliation(s)
| | - Evans Nyaboga
- Department of Biology, ETH Zurich, 8092 Zurich, Switzerland
| | | | | | - Jonas Grossmann
- Functional Genomics Center Zurich, UZH/ETH, 8057 Zurich, Switzerland
| | | | | | - Paolo Nanni
- Functional Genomics Center Zurich, UZH/ETH, 8057 Zurich, Switzerland
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Pruthvi V, Narasimhan R, Nataraja KN. Simultaneous expression of abiotic stress responsive transcription factors, AtDREB2A, AtHB7 and AtABF3 improves salinity and drought tolerance in peanut (Arachis hypogaea L.). PLoS One 2014. [PMID: 25474740 DOI: 10.1371/journal.pone.011115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023] Open
Abstract
Drought, salinity and extreme temperatures are the most common abiotic stresses, adversely affecting plant growth and productivity. Exposure of plants to stress activates stress signalling pathways that induce biochemical and physiological changes essential for stress acclimation. Stress tolerance is governed by multiple traits, and importance of a few traits in imparting tolerance has been demonstrated. Under drought, traits linked to water mining and water conservation, water use efficiency and cellular tolerance (CT) to desiccation are considered to be relevant. In this study, an attempt has been made to improve CT in drought hardy crop, peanut (Arachis hypogaea L., cv. TMV2) by co-expressing stress-responsive transcription factors (TFs), AtDREB2A, AtHB7 and AtABF3, associated with downstream gene expression. Transgenic plants simultaneously expressing these TFs showed increased tolerance to drought, salinity and oxidative stresses compared to wild type, with an increase in total plant biomass. The transgenic plants exhibited improved membrane and chlorophyll stability due to enhanced reactive oxygen species scavenging and osmotic adjustment by proline synthesis under stress. The improvement in stress tolerance in transgenic lines were associated with induced expression of various CT related genes like AhGlutaredoxin, AhAldehyde reductase, AhSerine threonine kinase like protein, AhRbx1, AhProline amino peptidase, AhHSP70, AhDIP and AhLea4. Taken together the results indicate that co-expression of stress responsive TFs can activate multiple CT pathways, and this strategy can be employed to improve abiotic stress tolerance in crop plants.
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Affiliation(s)
- Vittal Pruthvi
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
| | - Rama Narasimhan
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
| | - Karaba N Nataraja
- Department of Crop Physiology, University of Agricultural Sciences, Bangalore, Karnataka, India
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Nyaboga E, Njiru J, Nguu E, Gruissem W, Vanderschuren H, Tripathi L. Unlocking the potential of tropical root crop biotechnology in east Africa by establishing a genetic transformation platform for local farmer-preferred cassava cultivars. FRONTIERS IN PLANT SCIENCE 2013; 4:526. [PMID: 24400011 PMCID: PMC3872047 DOI: 10.3389/fpls.2013.00526] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/06/2013] [Indexed: 05/12/2023]
Abstract
Cassava genetic transformation capacity is still mostly restricted to advanced laboratories in the USA, Europe and China; and its implementation and maintenance in African laboratories has remained scarce. The impact of transgenic technologies for genetic improvement of cassava will depend largely on the transfer of such capabilities to researchers in Africa, where cassava has an important socioeconomic niche. A major constraint to the development of genetic transformation technologies for cassava improvement has been the lack of an efficient and robust transformation and regeneration system. Despite the success achieved in genetic modification of few cassava cultivars, including the model cultivar 60444, transgenic cassava production remains difficult for farmer-preferred cultivars. In this study, a protocol for cultivar 60444 developed at ETH Zurich was successfully implemented and optimized to establish transformation of farmer-preferred cassava cultivars popular in east Africa. The conditions for production and proliferation of friable embryogenic calli (FEC) and Agrobacterium-mediated transformation were optimized for three east African farmer-preferred cultivars (Ebwanatereka, Kibandameno and Serere). Our results demonstrated transformation efficiencies of about 14-22 independent transgenic lines per 100 mg of FEC for farmer-preferred cultivars in comparison to 28 lines per 100 mg of the model cultivar 60444. The presence, integration and expression of the transgenes were confirmed by PCR, Southern blot analysis and histochemical GUS assay. This study reports the establishment of a cassava transformation platform at International Institute of Tropical Agriculture (IITA) hosted by Biosciences eastern and central Africa (BecA) hub in Kenya and provides the basis for transferring important traits such as virus resistance and prolonged shelf-life to farmer-preferred cultivars in east Africa. We anticipate that such platform will also be instrumental to transfer technologies to national agricultural research systems (NARS) in sub-Saharan Africa.
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Affiliation(s)
- Evans Nyaboga
- International Institute of Tropical AgricultureNairobi, Kenya
- Department of Biology, Plant Biotechnology, Eidgenössische Technische HochschuleZurich, Switzerland
- Department of Biochemistry, University of NairobiNairobi, Kenya
| | - Joshua Njiru
- International Institute of Tropical AgricultureNairobi, Kenya
| | - Edward Nguu
- Department of Biochemistry, University of NairobiNairobi, Kenya
| | - Wilhelm Gruissem
- Department of Biology, Plant Biotechnology, Eidgenössische Technische HochschuleZurich, Switzerland
| | - Herve Vanderschuren
- Department of Biology, Plant Biotechnology, Eidgenössische Technische HochschuleZurich, Switzerland
| | - Leena Tripathi
- International Institute of Tropical AgricultureNairobi, Kenya
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127
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Xu J, Duan X, Yang J, Beeching JR, Zhang P. Coupled expression of Cu/Zn-superoxide dismutase and catalase in cassava improves tolerance against cold and drought stresses. PLANT SIGNALING & BEHAVIOR 2013; 8:e24525. [PMID: 23603959 PMCID: PMC3908942 DOI: 10.4161/psb.24525] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Recently we reported that the joint expression of cassava Cu/Zn superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) prolonged the shelf life of cassava storage-roots by the stabilization of reactive oxygen species (ROS) homeostasis after harvest. Since oxidative damage is a major feature of plants exposed to environmental stresses, transgenic cassava showing increased expression of the cytosolic MeCu/ZnSOD and the peroxisomal MeCAT1 should have improved resistance against other abiotic stresses. After cold treatment, the transgenic cassava maintained higher SOD and CAT activities and lower malendialdehyde content than those of wild type plants (WT). Detached leaves of transgenic cassava also showed slower transpirational water loss than those of WT. When plants were not watered for 30 d, transgenic lines exhibited a significant increase in water retention ability, accumulated 13% more proline and 12% less malendialdehyde than WT's, and showed enhanced activity of SOD and CAT. These results imply that manipulation of the antioxidative mechanism allows the development of staple crops with improved tolerance to abiotic stresses.
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Affiliation(s)
- Jia Xu
- 1 National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research; Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; Chinese Academy of Sciences; Shanghai, PR China
| | - Xiaoguang Duan
- 1 National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research; Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; Chinese Academy of Sciences; Shanghai, PR China
| | - Jun Yang
- 2 Shanghai Chenshan Plant Science Research Center; Chinese Academy of Sciences; Shanghai Chenshan Botanical Garden; Shanghai, PR China
| | - John R. Beeching
- 3 Department of Biology & Biochemistry; University of Bath; Bath, UK
| | - Peng Zhang
- 1 National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research; Institute of Plant Physiology and Ecology; Shanghai Institutes for Biological Sciences; Chinese Academy of Sciences; Shanghai, PR China
- 2 Shanghai Chenshan Plant Science Research Center; Chinese Academy of Sciences; Shanghai Chenshan Botanical Garden; Shanghai, PR China
- Correspondence to: Peng Zhang,
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128
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Xu J, Fellman J, Zhang P. Fluorescence Measurement of Postharvest Physiological Deterioration (PPD) in Cassava Storage Roots. Bio Protoc 2013. [DOI: 10.21769/bioprotoc.909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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