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Chen T, Hayes M, Liu Z, Isenegger D, Mason J, Spangenberg G. Modified fructan accumulation through overexpression of wheat fructan biosynthesis pathway fusion genes Ta1SST:Ta6SFT. BMC PLANT BIOLOGY 2024; 24:352. [PMID: 38689209 PMCID: PMC11059666 DOI: 10.1186/s12870-024-05049-w] [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: 02/03/2023] [Accepted: 04/19/2024] [Indexed: 05/02/2024]
Abstract
BACKGROUND Fructans are water-soluble carbohydrates that accumulate in wheat and are thought to contribute to a pool of stored carbon reserves used in grain filling and tolerance to abiotic stress. RESULTS In this study, transgenic wheat plants were engineered to overexpress a fusion of two fructan biosynthesis pathway genes, wheat sucrose: sucrose 1-fructosyltransferase (Ta1SST) and wheat sucrose: fructan 6-fructosyltransferase (Ta6SFT), regulated by a wheat ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit (TaRbcS) gene promoter. We have shown that T4 generation transgene-homozygous single-copy events accumulated more fructan polymers in leaf, stem and grain when compared in the same tissues from transgene null lines. Under water-deficit (WD) conditions, transgenic wheat plants showed an increased accumulation of fructan polymers with a high degree of polymerisation (DP) when compared to non-transgenic plants. In wheat grain of a transgenic event, increased deposition of particular fructan polymers such as, DP4 was observed. CONCLUSIONS This study demonstrated that the tissue-regulated expression of a gene fusion between Ta1SST and Ta6SFT resulted in modified fructan accumulation in transgenic wheat plants and was influenced by water-deficit stress conditions.
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Affiliation(s)
- Tong Chen
- Agriculture Victoria, Agribio, Bundoora, VIC, Australia
- School of Applied Systems Biology, La Trobe University, Bundoora, VIC, Australia
| | - Matthew Hayes
- Agriculture Victoria, Agribio, Bundoora, VIC, Australia
| | - Zhiqian Liu
- Agriculture Victoria, Agribio, Bundoora, VIC, Australia
| | | | - John Mason
- Agriculture Victoria, Agribio, Bundoora, VIC, Australia
- School of Applied Systems Biology, La Trobe University, Bundoora, VIC, Australia
| | - German Spangenberg
- Agriculture Victoria, Agribio, Bundoora, VIC, Australia
- School of Applied Systems Biology, La Trobe University, Bundoora, VIC, Australia
- Present Address: Qingdao Agricultural University, College of Grassland Science, N0. 700 Changcheng Road, Chengyang District, Qingdao, Shandong Province, 266109, P.R. China
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Kocaoglan EG, Radhakrishnan D, Nakayama N. Synthetic developmental biology: molecular tools to re-design plant shoots and roots. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:3864-3876. [PMID: 37155965 PMCID: PMC10826796 DOI: 10.1093/jxb/erad169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023]
Abstract
Plant morphology and anatomy strongly influence agricultural yield. Crop domestication has strived for desirable growth and developmental traits, such as larger and more fruits and semi-dwarf architecture. Genetic engineering has accelerated rational, purpose-driven engineering of plant development, but it can be unpredictable. Developmental pathways are complex and riddled with environmental and hormonal inputs, as well as feedback and feedforward interactions, which occur at specific times and places in a growing multicellular organism. Rational modification of plant development would probably benefit from precision engineering based on synthetic biology approaches. This review outlines recently developed synthetic biology technologies for plant systems and highlights their potential for engineering plant growth and development. Streamlined and high-capacity genetic construction methods (Golden Gate DNA Assembly frameworks and toolkits) allow fast and variation-series cloning of multigene transgene constructs. This, together with a suite of gene regulation tools (e.g. cell type-specific promoters, logic gates, and multiplex regulation systems), is starting to enable developmental pathway engineering with predictable outcomes in model plant and crop species.
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Affiliation(s)
- Elif Gediz Kocaoglan
- Department of Bioengineering, Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK
| | - Dhanya Radhakrishnan
- Department of Bioengineering, Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK
| | - Naomi Nakayama
- Department of Bioengineering, Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK
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3
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Tuncel A, Qi Y. CRISPR/Cas mediated genome editing in potato: Past achievements and future directions. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 325:111474. [PMID: 36174801 DOI: 10.1016/j.plantsci.2022.111474] [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: 06/20/2022] [Revised: 08/29/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Genome engineering has been re-shaping plant biotechnology and agriculture. Crop improvement using the recently developed gene editing techniques is now easier, faster, and more precise than ever. Although considered to be a global food security crop, potato has not benefitted enough from diverse collection of these techniques. Unique genetic features of cultivated potatoes such as tetrasomic inheritance, high genomic heterozygosity, and inbreeding depression hamper conventional breeding of this important crop. Therefore, genome editing provides an excellent arsenal of tools for trait improvement in potato. Moreover, using specific transformation protocols, it is possible to engineer transgene free commercial varieties. In this review we first describe the past achievements in potato genome editing and highlight some of the missing aspects of these efforts. Then, we discuss about technical challenges of genome editing in potato and present approaches to overcome these difficulties. Finally, we talk about genome editing applications that have not been explored in potato and point out some of the missing venues in literature.
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Affiliation(s)
- Aytug Tuncel
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA.
| | - Yiping Qi
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, USA; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, USA.
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4
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Ma X, Zeng W, Wang L, Cheng R, Zhao Z, Huang C, Sun Z, Tao P, Wang T, Zhang J, Liu L, Duan X, Niu D. Validation of reliable safe harbor locus for efficient porcine transgenesis. Funct Integr Genomics 2022; 22:553-563. [PMID: 35412198 DOI: 10.1007/s10142-022-00859-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 11/30/2022]
Abstract
Transgenic technology is now widely used in biomedical and agricultural fields. Transgenesis is commonly achieved through random integration which might cause some uncertain consequences. The site-specific integration could avoid this disadvantage. This study aimed to screen and validate the best safe harbor (SH) locus for efficient porcine transgenesis. First, the cells carrying the EGFP reporter construct at four different SH loci (ROSA26, AAVS1, H11 and COL1A1) were achieved through CRSIPR/Cas9-mediated HDR. At the COL1A1 and ROSA26 loci, a higher mRNA and protein expression of EGFP was detected, and it was correlated with a lower level of DNA methylation of the EGFP promoter, hEF1α. A decreased H3K27me3 modification of the hEF1α promoter at the COL1A1 locus was also detected. For the safety of transgenesis at different SH locus, we found that transgenesis could relatively alter the expression of the adjacent endogenous genes, but the influence was limited. We also did not observe any off-target cleavage for the selected sgRNAs of the COL1A1 and ROSA26 loci. In conclusion, the COL1A1 and ROSA26 were confirmed to be the best two SH loci with the COL1A1 being more competitive for porcine transgenesis. This work would greatly facilitate porcine genome engineering and transgenic pig production.
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Affiliation(s)
- Xiang Ma
- Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, 666 Wusu street, Lin'an District, Hangzhou, 311300, Zhejiang, China
| | - Weijun Zeng
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Lei Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Rui Cheng
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Zeying Zhao
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Caiyun Huang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Zhongxin Sun
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Peipei Tao
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Tao Wang
- Nanjing Kgene Genetic Engineering Co., Ltd, Nanjing, 211300, Jiangsu, China
| | - Jufang Zhang
- Cosmetic and Plastic Surgery Department, Hangzhou First People's Hospital, Hangzhou, 310006, Zhejiang, China
| | - Lu Liu
- Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, 666 Wusu street, Lin'an District, Hangzhou, 311300, Zhejiang, China.
| | - Xing Duan
- Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, 666 Wusu street, Lin'an District, Hangzhou, 311300, Zhejiang, China.
| | - Dong Niu
- Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, 666 Wusu street, Lin'an District, Hangzhou, 311300, Zhejiang, China.
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5
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Nitarska D, Boehm R, Debener T, Lucaciu RC, Halbwirth H. First genome edited poinsettias: targeted mutagenesis of flavonoid 3'-hydroxylase using CRISPR/Cas9 results in a colour shift. PLANT CELL, TISSUE AND ORGAN CULTURE 2021; 147:49-60. [PMID: 34776565 PMCID: PMC8550517 DOI: 10.1007/s11240-021-02103-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/07/2021] [Indexed: 06/01/2023]
Abstract
UNLABELLED The CRISPR/Cas9 system is a remarkably promising tool for targeted gene mutagenesis, and becoming ever more popular for modification of ornamental plants. In this study we performed the knockout of flavonoid 3'-hydroxylase (F3'H) with application of CRISPR/Cas9 in the red flowering poinsettia (Euphorbia pulcherrima) cultivar 'Christmas Eve', in order to obtain plants with orange bract colour, which accumulate prevalently pelargonidin. F3'H is an enzyme that is necessary for formation of cyanidin type anthocyanins, which are responsible for the red colour of poinsettia bracts. Even though F3'H was not completely inactivated, the bract colour of transgenic plants changed from vivid red (RHS 45B) to vivid reddish orange (RHS 33A), and cyanidin levels decreased significantly compared with the wild type. In the genetically modified plants, an increased ratio of pelargonidin to cyanidin was observed. By cloning and expression of mutated proteins, the lack of F3'H activity was confirmed. This confirms that a loss of function mutation in the poinsettia F3'H gene is sufficient for obtaining poinsettia with orange bract colour. This is the first report of successful use of CRISPR/Cas9 for genome editing in poinsettia. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s11240-021-02103-5.
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Affiliation(s)
- Daria Nitarska
- Institute of Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, 1060 Vienna, Austria
| | | | - Thomas Debener
- Institute of Plant Genetics, Leibniz Universität Hannover, 30419 Hannover, Germany
| | - Rares Calin Lucaciu
- Institute of Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, 1060 Vienna, Austria
| | - Heidi Halbwirth
- Institute of Chemical, Environmental and Bioscience Engineering, Technische Universität Wien, 1060 Vienna, Austria
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Xu XY, Akbar S, Shrestha P, Venugoban L, Devilla R, Hussain D, Lee J, Rug M, Tian L, Vanhercke T, Singh SP, Li Z, Sharp PJ, Liu Q. A Synergistic Genetic Engineering Strategy Induced Triacylglycerol Accumulation in Potato ( Solanum tuberosum) Leaf. FRONTIERS IN PLANT SCIENCE 2020; 11:215. [PMID: 32210994 PMCID: PMC7069356 DOI: 10.3389/fpls.2020.00215] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 02/12/2020] [Indexed: 05/23/2023]
Abstract
Potato is the 4th largest staple food in the world currently. As a high biomass crop, potato harbors excellent potential to produce energy-rich compounds such as triacylglycerol as a valuable co-product. We have previously reported that transgenic potato tubers overexpressing WRINKLED1, DIACYLGLYCEROL ACYLTRANSFERASE 1, and OLEOSIN genes produced considerable levels of triacylglycerol. In this study, the same genetic engineering strategy was employed on potato leaves. The overexpression of Arabidopsis thaliana WRINKED1 under the transcriptional control of a senescence-inducible promoter together with Arabidopsis thaliana DIACYLGLYCEROL ACYLTRANSFERASE 1 and Sesamum indicum OLEOSIN driven by the Cauliflower Mosaic Virus 35S promoter and small subunit of Rubisco promoter respectively, resulted in an approximately 30- fold enhancement of triacylglycerols in the senescent transgenic potato leaves compared to the wild type. The increase of triacylglycerol in the transgenic potato leaves was accompanied by perturbations of carbohydrate accumulation, apparent in a reduction in starch content and increased total soluble sugars, as well as changes of polar membrane lipids at different developmental stages. Microscopic and biochemical analysis further indicated that triacylglycerols and lipid droplets could not be produced in chloroplasts, despite the increase and enlargement of plastoglobuli at the senescent stage. Possibly enhanced accumulation of fatty acid phytyl esters in the plastoglobuli were reflected in transgenic potato leaves relative to wild type. It is likely that the plastoglobuli may have hijacked some of the carbon as the result of WRINKED1 expression, which could be a potential factor restricting the effective accumulation of triacylglycerols in potato leaves. Increased lipid production was also observed in potato tubers, which may have affected the tuberization to a certain extent. The expression of transgenes in potato leaf not only altered the carbon partitioning in the photosynthetic source tissue, but also the underground sink organs which highly relies on the leaves in development and energy deposition.
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Affiliation(s)
- Xiao-yu Xu
- CSIRO Agriculture and Food, Canberra, ACT, Australia
- Plant Breeding Institute and Sydney Institute of Agriculture, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
| | - Sehrish Akbar
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | | | | | | | - Dawar Hussain
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Jiwon Lee
- Center for Advanced Microscopy, The Australian National University, Canberra, ACT, Australia
| | - Melanie Rug
- Center for Advanced Microscopy, The Australian National University, Canberra, ACT, Australia
| | - Lijun Tian
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | | | | | - Zhongyi Li
- CSIRO Agriculture and Food, Canberra, ACT, Australia
| | - Peter J. Sharp
- Plant Breeding Institute and Sydney Institute of Agriculture, School of Life and Environmental Sciences, The University of Sydney, Camperdown, NSW, Australia
| | - Qing Liu
- CSIRO Agriculture and Food, Canberra, ACT, Australia
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7
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Patterson EL, Saski CA, Sloan DB, Tranel PJ, Westra P, Gaines TA. The Draft Genome of Kochia scoparia and the Mechanism of Glyphosate Resistance via Transposon-Mediated EPSPS Tandem Gene Duplication. Genome Biol Evol 2019; 11:2927-2940. [PMID: 31518388 PMCID: PMC6808082 DOI: 10.1093/gbe/evz198] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2019] [Indexed: 12/14/2022] Open
Abstract
Increased copy number of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene confers resistance to glyphosate, the world's most-used herbicide. There are typically three to eight EPSPS copies arranged in tandem in glyphosate-resistant populations of the weed kochia (Kochia scoparia). Here, we report a draft genome assembly from a glyphosate-susceptible kochia individual. Additionally, we assembled the EPSPS locus from a glyphosate-resistant kochia plant by sequencing select bacterial artificial chromosomes from a kochia bacterial artificial chromosome library. Comparing the resistant and susceptible EPSPS locus allowed us to reconstruct the history of duplication in the structurally complex EPSPS locus and uncover the genes that are coduplicated with EPSPS, several of which have a corresponding change in transcription. The comparison between the susceptible and resistant assemblies revealed two dominant repeat types. Additionally, we discovered a mobile genetic element with a FHY3/FAR1-like gene predicted in its sequence that is associated with the duplicated EPSPS gene copies in the resistant line. We present a hypothetical model based on unequal crossing over that implicates this mobile element as responsible for the origin of the EPSPS gene duplication event and the evolution of herbicide resistance in this system. These findings add to our understanding of stress resistance evolution and provide an example of rapid resistance evolution to high levels of environmental stress.
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Affiliation(s)
- Eric L Patterson
- Department of Bioagricultural Sciences and Pest Management, Colorado State University
- Department of Genetics and Biochemistry, Clemson University
| | | | | | | | - Philip Westra
- Department of Bioagricultural Sciences and Pest Management, Colorado State University
| | - Todd A Gaines
- Department of Bioagricultural Sciences and Pest Management, Colorado State University
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Yevtushenko DP, Misra S. Spatiotemporal activities of Douglas-fir BiP Pro1 promoter in transgenic potato. PLANTA 2018; 248:1569-1579. [PMID: 30276470 DOI: 10.1007/s00425-018-3013-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 09/20/2018] [Indexed: 06/08/2023]
Abstract
The PmBiPPro1 promoter of the luminal binding protein (BiP) from Douglas-fir is fully functional in transgenic potato, responsive to wounding, and has high transcriptional activity in tubers. A predefined pattern and level of transgene expression targeted to specific tissues or organs and at a particular developmental stage is a pre-requisite for the successful development of plants with desired traits. Here, we evaluated the transcriptional activity of the PmBiPPro1 promoter of the luminal binding protein (BiP) from Douglas-fir, by expressing reporter β-D-glucuronidase (GUS) gene constructs containing three different PmBiPPro1 promoter versions (2258 bp, 1259 bp, and 278 bp) in transgenic potato. In conifers, this promoter regulates the endoplasmic reticulum (ER) molecular chaperon of the HSP70 stress-related protein family and is essential for proper functioning of the ER. Stable expression analysis demonstrated that two of three PmBiPPro1 promoter versions (PmBiPPro1-1 and PmBiPPro1-3) were fully functional in the heterologous host, exhibited high transcriptional activities in the leaves of unstressed potatoes, and were responsive to wounding. Deletion analysis showed that the positive cis-active regulatory elements necessary for higher level expression resided within the - 1243 to - 261 region, whereas negative cis-active elements encompassed nucleotides - 2242 to - 1243. Histochemical staining revealed high level of GUS activities in tissues associated with a high rate of cell division and secretory activities. Most importantly, the PmBiPPro1 promoters, especially the full-length version, had activity in microtubers at a level that was much higher than in any other potato organ or tissue. The - 2242 to - 1243 bp region likely contains important cis element(s) that interact with tuber-specific transcription factors required for promoter activation in the storage organs. The organ-specific activity of the PmBiPPro1 promoters may be useful for targeted expression of heterologous molecules in potato tubers.
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Affiliation(s)
- Dmytro P Yevtushenko
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, T1K 3M4, Canada.
| | - Santosh Misra
- Department of Biochemistry and Microbiology, Centre for Forest Biology, University of Victoria, Victoria, BC, V8W 3P6, Canada
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Expression of hybrid fusion protein (Cry1Ac::ASAL) in transgenic rice plants imparts resistance against multiple insect pests. Sci Rep 2018; 8:8458. [PMID: 29855556 PMCID: PMC5981619 DOI: 10.1038/s41598-018-26881-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 05/21/2018] [Indexed: 12/18/2022] Open
Abstract
To evolve rice varieties resistant to different groups of insect pests a fusion gene, comprising DI and DII domains of Bt Cry1Ac and carbohydrate binding domain of garlic lectin (ASAL), was constructed. Transgenic rice lines were generated and evaluated to assess the efficacy of Cry1Ac::ASAL fusion protein against three major pests, viz., yellow stem borer (YSB), leaf folder (LF) and brown planthopper (BPH). Molecular analyses of transgenic plants revealed stable integration and expression of the fusion gene. In planta insect bioassays on transgenics disclosed enhanced levels of resistance compared to the control plants. High insect mortality of YSB, LF and BPH was observed on transgenics compared to that of control plants. Furthermore, honeydew assays revealed significant decreases in the feeding ability of BPH on transgenic plants as compared to the controls. Ligand blot analysis, using BPH insects fed on cry1Ac::asal transgenic rice plants, revealed a modified receptor protein-binding pattern owing to its ability to bind to additional receptors in insects. The overall results authenticate that Cry1Ac::ASAL protein is endowed with remarkable entomotoxic effects against major lepidopteran and hemipteran insects. As such, the fusion gene appears promising and can be introduced into various other crops to control multiple insect pests.
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10
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Kahlon JG, Jacobsen HJ, Chatterton S, Hassan F, Bowness R, Hall LM. Lack of efficacy of transgenic pea (Pisum sativum L.) stably expressing antifungal genes against Fusarium spp. in three years of confined field trials. GM CROPS & FOOD 2018; 9:90-108. [PMID: 29590003 PMCID: PMC6277066 DOI: 10.1080/21645698.2018.1445471] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 02/09/2018] [Accepted: 02/12/2018] [Indexed: 10/17/2022]
Abstract
Fusarium root rot is a major pea disease in Canada and only partial tolerance exists in germplasm. Transgenic technologies may hold promise but the economic benefits of genetically modified (GM) pea will need to surpass the regulatory costs, time and labor involved in bringing a GM crop to market. European pea (Pisum sativum L.) cultivars expressing four antifungal genes, 1-3 β glucanase (G), endochitinase (C) (belonging to PR proteins family), polygalacturonase inhibiting proteins (PGIPs) (P) and stilbene synthase (V) have been transformed for disease tolerance and showed disease tolerance under laboratory conditions. Transgenic lines with four antifungal genes inserted either individually or stacked through crossing were tested for their efficacy against Fusarium root rot (Fusarium avenaceum) in confined trials over three years (2013 to 2015) in comparison with two parental German lines and three Canadian lines. Superior emergence, higher fresh weight or lower disease ratings above and below ground, of transgenic lines in presence of disease inoculum were not observed consistently in the three years of field experiments when compared to the parental and Canadian lines in the presence of disease inoculum. No indication of an advantage of stacked genes over single genes was observed. Most transgenic lines had lower relative gene expression in the roots than in the leaves in greenhouse trials suggesting a possible explanation for poor tolerance to Fusarium root rot. Field trials are necessary to verify the agronomic performance and ecological relevance of the promising effects detected under laboratory conditions.
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Affiliation(s)
- Jagroop Gill Kahlon
- Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, AB, Canada
| | - Hans-Jörg Jacobsen
- Institute for Plant Genetics, Gottfried Wilhelm Leibniz Universität Hannover, Herrenhäuser Str. 2, Hannover, Germany
| | - Syama Chatterton
- Agriculture and Agri-food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Fathi Hassan
- Institute for Plant Genetics, Gottfried Wilhelm Leibniz Universität Hannover, Herrenhäuser Str. 2, Hannover, Germany
| | - Robyne Bowness
- Alberta Agriculture and Rural Development, Lacombe, AB, Canada
| | - Linda M. Hall
- Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, AB, Canada
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Ren Y, Zhang J, Wang G, Liu X, Li L, Wang J, Yang M. The Relationship between Insect Resistance and Tree Age of Transgenic Triploid Populus tomentosa Plants. FRONTIERS IN PLANT SCIENCE 2018; 9:53. [PMID: 29434618 PMCID: PMC5790799 DOI: 10.3389/fpls.2018.00053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/10/2018] [Indexed: 05/03/2023]
Abstract
To explore the stability of insect resistance during the development of transgenic insect-resistant trees, this study investigated how insect resistance changes as transgenic trees age. We selected 19 transgenic insect-resistant triploid Populus tomentosa lines as plant material. The presence of exogenous genes and Cry1Ac protein expression were verified using polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) analyses. The toxicity for Clostera anachoreta and Lymantria dispar was evaluated by feeding fresh leaves to first instar larvae after the trees were planted in the field for 2 years and after the sixth year. Results of PCR showed that the exogenous genes had a long-term presence in the poplar genome. ELISA analyses showed significant differences existed on the 6-year-old transgenic lines. The insect-feeding experiment demonstrated significant differences in the mortality rates of C. anachoreta and L. dispar among different transgenic lines. The average corrected mortality rates of C. anachoreta and L. dispar ranged from 5.6-98.7% to 35.4-7.2% respectively. The larval mortality rates differed significantly between the lines at different ages. Up to 52.6% of 1-year-old transgenic lines and 42.1% of 2-year-old transgenic lines caused C. anachoreta larval mortality rates to exceed 80%, whereas only 26.3% of the 6-year-old transgenic lines. The mortality rates of L. dispar exhibited the same trend: 89.5% of 1-year-old transgenic lines and 84.2% of 2-year-old transgenic lines caused L. dispar larval mortality rates to exceed 80%; this number decreased to 63.2% for the 6-year-old plants. The proportion of 6-year-old trees with over 80% larval mortality rates was clearly lower than that of the younger trees. The death distribution of C. anachoreta in different developmental stages also showed the larvae that fed on the leaves of 1-year-old trees were killed mostly during L1 and L2 stages, whereas the proportion of larvae that died in L3 and L4 stages was significantly increased when fed on leaves of 6-year-old trees. Results of correlation analysis showed there was a significant correlation between the larvae mortality rates of trees at different ages, as well as between Cry1Ac protein contents and larvae mortality rates of 6-year-old trees.
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Affiliation(s)
- Yachao Ren
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
- Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, Baoding, China
| | - Jun Zhang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
- Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, Baoding, China
| | - Guiying Wang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
- Langfang Academy of Agriculture and Forestry Sciences, Langfang, China
| | - Xiaojie Liu
- Langfang Academy of Agriculture and Forestry Sciences, Langfang, China
| | - Li Li
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
| | - Jinmao Wang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
- Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, Baoding, China
| | - Minsheng Yang
- Forest Department, Forestry College, Hebei Agricultural University, Baoding, China
- Hebei Key Laboratory for Tree Genetic Resources and Forest Protection, Baoding, China
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Weinhold A. Transgenerational stress-adaption: an opportunity for ecological epigenetics. PLANT CELL REPORTS 2018; 37:3-9. [PMID: 29032426 DOI: 10.1007/s00299-017-2216-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/04/2017] [Indexed: 05/14/2023]
Abstract
In the recent years, there has been considerable interest to investigate the adaptive transgenerational plasticity of plants and how a "stress memory" can be transmitted to the following generation. Although, increasing evidence suggests that transgenerational adaptive responses have widespread ecological relevance, the underlying epigenetic processes have rarely been elucidated. On the other hand, model plant species have been deeply investigated in their genome-wide methylation landscape without connecting this to the ecological reality of the plant. What we need is the combination of an ecological understanding which plant species would benefit from transgenerational epigenetic stress-adaption in their natural habitat, combined with a deeper molecular analysis of non-model organisms. Only such interdisciplinary linkage in an ecological epigenetic study could unravel the full potential that epigenetics could play for the transgenerational stress-adaption of plants.
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Affiliation(s)
- Arne Weinhold
- Applied Zoology/Animal Ecology, Dahlem Centre of Plant Sciences (DCPS), Institute of Biology, FU Berlin, Haderslebener Str. 9, 12163, Berlin, Germany.
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Kahlon JG, Jacobsen HJ, Cahill JF, Hall LM. Antifungal genes expressed in transgenic pea (Pisum sativum L.) do not affect root colonization of arbuscular mycorrhizae fungi. MYCORRHIZA 2017; 27:683-694. [PMID: 28608039 DOI: 10.1007/s00572-017-0781-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 05/21/2017] [Indexed: 06/07/2023]
Abstract
Genetically modified crops have raised concerns about unintended consequences on non-target organisms including beneficial soil associates. Pea transformed with four antifungal genes 1-3 β glucanase, endochitinase, polygalacturonase-inhibiting proteins, and stilbene synthase is currently under field-testing for efficacy against fungal diseases in Canada. Transgenes had lower expression in the roots than leaves in greenhouse experiment. To determine the impact of disease-tolerant pea or gene products on colonization by non-target arbuscular mycorrhizae and nodulation by rhizobium, a field trial was established. Transgene insertion, as single gene or stacked genes, did not alter root colonization by arbuscular mycorrhiza fungus (AMF) or root nodulation by rhizobium inoculation in the field. We found no effect of transgenes on the plant growth and performance although, having a dual inoculant with both AMF and rhizobium yielded higher fresh weight shoot-to-root ratio in all the lines tested. This initial risk assessment of transgenic peas expressing antifungal genes showed no deleterious effect on non-target organisms.
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Affiliation(s)
- Jagroop Gill Kahlon
- Agricultural, Food and Nutritional Sciences, 410 Agriculture/Forestry, University of Alberta, Edmonton, T6K 2P5, Canada.
| | - Hans-Jörg Jacobsen
- Institute for Plant Genetics, Section of Plant Biotechnology, Gottfried Wilhelm Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - James F Cahill
- Department of Biological sciences, B717a, Biological Sciences Bldg., University of Alberta, Edmonton, Alberta, T6G 2E9, Canada
| | - Linda M Hall
- Agricultural, Food and Nutritional Sciences, 410 Agriculture/Forestry, University of Alberta, Edmonton, T6K 2P5, Canada
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Teressa Negawo A, Baranek L, Jacobsen HJ, Hassan F. Molecular and functional characterization of cry1Ac transgenic pea lines. GM CROPS & FOOD 2016; 7:159-174. [PMID: 27764552 PMCID: PMC5161004 DOI: 10.1080/21645698.2016.1240148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/16/2016] [Accepted: 09/20/2016] [Indexed: 10/20/2022]
Abstract
Transgenic pea lines transformed with the cry1Ac gene were characterized at molecular (PCR, RT-PCR, qRT-PCR and immunostrip assay) and functional levels (leaf paint and insect feeding bioassays). The results showed the presence, expression, inheritance and functionality of the introduced transgene at different progeny levels. Variation in the expression of the cry1Ac gene was observed among the different transgenic lines. In the insect bioassay studies using the larvae of Heliothis virescens, both larval survival and plant damage were highly affected on the different transgenic plants. Up to 100 % larval mortality was observed on the transgenic plants compared to 17.42 % on control plants. Most of the challenged transgenic plants showed very negligible to substantially reduced feeding damage indicating the insect resistance of the developed transgenic lines. Further analysis under field condition will be required to select promising lines for future uses.
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Affiliation(s)
- Alemayehu Teressa Negawo
- Institute for Plant Genetics (Section of Plant Biotechnology), Gottfried Wilhelm Leibniz University of Hannover, Hannover, Germany
- International Livestock Research Institute, Addis Ababa, Ethiopia
| | - Linda Baranek
- Institute for Plant Genetics (Section of Plant Biotechnology), Gottfried Wilhelm Leibniz University of Hannover, Hannover, Germany
| | - Hans-Jörg Jacobsen
- Institute for Plant Genetics (Section of Plant Biotechnology), Gottfried Wilhelm Leibniz University of Hannover, Hannover, Germany
| | - Fathi Hassan
- Institute for Plant Genetics (Section of Plant Biotechnology), Gottfried Wilhelm Leibniz University of Hannover, Hannover, Germany
- Laboratory for experimental trauma Surgery, Justus-Liebig University of Giessen, Giessen, Germany
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15
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Enhanced resistance to Sclerotinia sclerotiorum in Brassica napus by co-expression of defensin and chimeric chitinase genes. J Appl Genet 2016; 57:417-425. [PMID: 26862081 DOI: 10.1007/s13353-016-0340-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 01/19/2016] [Accepted: 01/25/2016] [Indexed: 01/19/2023]
Abstract
Sclerotinia stem rot caused by Sclerotinia sclerotiorum is one of the major fungal diseases of Brassica napus L. To develop resistance against this fungal disease, the defensin gene from Raphanus sativus and chimeric chit42 from Trichoderma atroviride with a C-terminal fused chitin-binding domain from Serratia marcescens were co-expressed in canola via Agrobacterium-mediated transformation. Twenty transformants were confirmed to carry the two transgenes as detected by polymerase chain reaction (PCR), with 4.8 % transformation efficiency. The chitinase activity of PCR-positive transgenic plants were measured in the presence of colloidal chitin, and five transgenic lines showing the highest chitinase activity were selected for checking the copy number of the transgenes through Southern blot hybridisation. Two plants carried a single copy of the transgenes, while the remainder carried either two or three copies of the transgenes. The antifungal activity of two transgenic lines that carried a single copy of the transgenes (T4 and T10) was studied by a radial diffusion assay. It was observed that the constitutive expression of these transgenes in the T4 and T10 transgenic lines suppressed the growth of S. sclerotiorum by 49 % and 47 %, respectively. The two transgenic lines were then let to self-pollinate to produce the T2 generation. Greenhouse bioassays were performed on the transgenic T2 young leaves by challenging with S. sclerotiorum and the results revealed that the expression of defensin and chimeric chitinase from a heterologous source in canola demonstrated enhanced resistance against sclerotinia stem rot disease.
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Rustagi A, Kumar D, Shekhar S, Yusuf MA, Misra S, Sarin NB. Transgenic Brassica juncea plants expressing MsrA1, a synthetic cationic antimicrobial peptide, exhibit resistance to fungal phytopathogens. Mol Biotechnol 2014; 56:535-45. [PMID: 24452332 DOI: 10.1007/s12033-013-9727-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cationic antimicrobial peptides (CAPs) have shown potential against broad spectrum of phytopathogens. Synthetic versions with desirable properties have been modeled on these natural peptides. MsrA1 is a synthetic chimera of cecropin A and melittin CAPs with antimicrobial properties. We generated transgenic Brassica juncea plants expressing the msrA1 gene aimed at conferring fungal resistance. Five independent transgenic lines were evaluated for resistance to Alternaria brassicae and Sclerotinia sclerotiorum, two of the most devastating pathogens of B. juncea crops. In vitro assays showed inhibition by MsrA1 of Alternaria hyphae growth by 44-62 %. As assessed by the number and size of lesions and time taken for complete leaf necrosis, the Alternaria infection was delayed and restricted in the transgenic plants with the protection varying from 69 to 85 % in different transgenic lines. In case of S. sclerotiorum infection, the lesions were more severe and spread profusely in untransformed control compared with transgenic plants. The sclerotia formed in the stem of untransformed control plants were significantly more in number and larger in size than those present in the transgenic plants where disease protection of 56-71.5 % was obtained. We discuss the potential of engineering broad spectrum biotic stress tolerance by transgenic expression of CAPs in crop plants.
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Affiliation(s)
- Anjana Rustagi
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
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Kamenarova K, Gecheff K, Stoyanova M, Muhovski Y, Anzai H, Atanassov A. Production of Recombinant Human Lactoferin in Transgenic Barley. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2007.10817407] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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18
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Calin A, Cucu N, Tessio C. Stability of a Transgene in Potato Depends on Endogenous Plant Tissue Factors. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.1996.10818891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Ramineni R, Sadumpati V, Khareedu VR, Vudem DR. Transgenic pearl millet male fertility restorer line (ICMP451) and hybrid (ICMH451) expressing Brassica juncea Nonexpressor of pathogenesis related genes 1 (BjNPR1) exhibit resistance to downy mildew disease. PLoS One 2014; 9:e90839. [PMID: 24603762 PMCID: PMC3946217 DOI: 10.1371/journal.pone.0090839] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 02/05/2014] [Indexed: 11/30/2022] Open
Abstract
Brassica juncea Nonexpressor of pathogenesis-related genes 1 (BjNPR1) has been introduced into pearl millet male fertility restorer line ICMP451 by Agrobacterium tumefaciens-mediated genetic transformation. Transgenic pearl millet plants were regenerated from the phosphinothricin-resistant calli obtained after co-cultivation with A. tumefaciens strain LBA4404 harbouring Ti plasmid pSB111-bar-BjNPR1. Molecular analyses confirmed the stable integration and expression of BjNPR1 in transgenic pearl millet lines. Transgenes BjNPR1 and bar were stably inherited and disclosed co-segregation in subsequent generations in a Mendelian fashion. Transgenic pearl millet hybrid ICMH451-BjNPR1 was developed by crossing male-sterile line 81A X homozygous transgenic line ICMP451-BjNPR1. T3 and T4 homozygous lines of ICMP451-BjNPR1 and hybrid ICMH451-BjNPR1 exhibited resistance to three strains of downy mildew pathogen, while the untransformed ICMP451 and the isogenic hybrid ICMH451 plants were found susceptible. Following infection with S. graminicola, differential expression of systemic acquired resistance pathway genes, UDP-glucose salicylic acid glucosyl transferase and pathogenesis related gene 1 was observed in transgenic ICMP451-BjNPR1 and untransformed plants indicating the activation of systemic acquired resistance pathway contributing to the transgene-mediated resistance against downy mildew. The transgenic pearl millet expressing BjNPR1 showed resistance to multiple strains of S. graminicola and, as such, seems promising for the development of durable downy mildew resistant hybrids.
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Affiliation(s)
- Ramadevi Ramineni
- Centre for Plant Molecular Biology, Osmania University, Hyderabad, Andhra Pradesh, India
| | - Vijayakumar Sadumpati
- Centre for Plant Molecular Biology, Osmania University, Hyderabad, Andhra Pradesh, India
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Ntui VO, Kong K, Azadi P, Khan RS, Chin DP, Igawa T, Mii M, Nakamura I. RNAi-Mediated Resistance to Cucumber Mosaic Virus (CMV) in Genetically Engineered Tomato. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/ajps.2014.55071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Maessen G. Genomic stability and stability of expression in genetically modified plants. ACTA ACUST UNITED AC 2013. [DOI: 10.1111/plb.1997.46.1.3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Vajhala CSK, Sadumpati VK, Nunna HR, Puligundla SK, Vudem DR, Khareedu VR. Development of transgenic cotton lines expressing Allium sativum agglutinin (ASAL) for enhanced resistance against major sap-sucking pests. PLoS One 2013; 8:e72542. [PMID: 24023750 PMCID: PMC3762794 DOI: 10.1371/journal.pone.0072542] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/10/2013] [Indexed: 12/29/2022] Open
Abstract
Mannose-specific Allium sativum leaf agglutinin encoding gene (ASAL) and herbicide tolerance gene (BAR) were introduced into an elite cotton inbred line (NC-601) employing Agrobacterium-mediated genetic transformation. Cotton transformants were produced from the phosphinothricin (PPT)-resistant shoots obtained after co-cultivation of mature embryos with the Agrobacterium strain EHA105 harbouring recombinant binary vector pCAMBIA3300-ASAL-BAR. PCR and Southern blot analysis confirmed the presence and stable integration of ASAL and BAR genes in various transformants of cotton. Basta leaf-dip assay, northern blot, western blot and ELISA analyses disclosed variable expression of BAR and ASAL transgenes in different transformants. Transgenes, ASAL and BAR, were stably inherited and showed co-segregation in T1 generation in a Mendelian fashion for both PPT tolerance and insect resistance. In planta insect bioassays on T2 and T3 homozygous ASAL-transgenic lines revealed potent entomotoxic effects of ASAL on jassid and whitefly insects, as evidenced by significant decreases in the survival, development and fecundity of the insects when compared to the untransformed controls. Furthermore, the transgenic cotton lines conferred higher levels of resistance (1-2 score) with minimal plant damage against these major sucking pests when bioassays were carried out employing standard screening techniques. The developed transgenics could serve as a potential genetic resource in recombination breeding aimed at improving the pest resistance of cotton. This study represents the first report of its kind dealing with the development of transgenic cotton resistant to two major sap-sucking insects.
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Affiliation(s)
| | - Vijaya Kumar Sadumpati
- Centre for Plant Molecular Biology, Osmania University, Hyderabad, Andhra Pradesh, India
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Weinhold A, Kallenbach M, Baldwin IT. Progressive 35S promoter methylation increases rapidly during vegetative development in transgenic Nicotiana attenuata plants. BMC PLANT BIOLOGY 2013; 13:99. [PMID: 23837904 PMCID: PMC3716894 DOI: 10.1186/1471-2229-13-99] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 07/06/2013] [Indexed: 05/23/2023]
Abstract
BACKGROUND Genetically modified plants are widely used in agriculture and increasingly in ecological research to enable the selective manipulation of plant traits in the field. Despite their broad usage, many aspects of unwanted transgene silencing throughout plant development are still poorly understood. A transgene can be epigenetically silenced by a process called RNA directed DNA methylation (RdDM), which can be seen as a heritable loss of gene expression. The spontaneous nature of transgene silencing has been widely reported, but patterns of acquirement remain still unclear. RESULTS Transgenic wild tobacco plants (Nicotiana attenuata) expressing heterologous genes coding for antimicrobial peptides displayed an erratic and variable occurrence of transgene silencing. We focused on three independently transformed lines (PNA 1.2, PNA 10.1 and ICE 4.4) as they rapidly lost the expression of the resistance marker and down-regulated transgene expression by more than 200 fold after only one plant generation. Bisulfite sequencing indicated hypermethylation within the 35S and NOS promoters of these lines. To shed light on the progress of methylation establishment, we successively sampled leaf tissues from different stages during plant development and found a rapid increase in 35S promoter methylation during vegetative growth (up to 77% absolute increase within 45 days of growth). The levels of de novo methylation were inherited by the offspring without any visible discontinuation. A secondary callus regeneration step could interfere with the establishment of gene silencing and we found successfully restored transgene expression in the offspring of several regenerants. CONCLUSIONS The unpredictability of the gene silencing process requires a thorough selection and early detection of unstable plant lines. De novo methylation of the transgenes was acquired solely during vegetative development and did not require a generational change for its establishment or enhancement. A secondary callus regeneration step provides a convenient way to rescue transgene expression without causing undesirable morphological effects, which is essential for experiments that use transformed plants in the analysis of ecologically important traits.
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Affiliation(s)
- Arne Weinhold
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, Jena 07745, Germany
| | - Mario Kallenbach
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, Jena 07745, Germany
| | - Ian Thomas Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, Jena 07745, Germany
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Gutiérrez SP, Saberianfar R, Kohalmi SE, Menassa R. Protein body formation in stable transgenic tobacco expressing elastin-like polypeptide and hydrophobin fusion proteins. BMC Biotechnol 2013; 13:40. [PMID: 23663656 PMCID: PMC3659085 DOI: 10.1186/1472-6750-13-40] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/06/2013] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Plants are recognized as an efficient and inexpensive system to produce valuable recombinant proteins. Two different strategies have been commonly used for the expression of recombinant proteins in plants: transient expression mediated by Agrobacterium; or stable transformation of the plant genome. However, the use of plants as bioreactors still faces two main limitations: low accumulation levels of some recombinant proteins and lack of efficient purification methods. Elastin-like polypeptide (ELP), hydrophobin I (HFBI) and Zera® are three fusion partners found to increase the accumulation levels of recombinant proteins and induce the formation of protein bodies (PBs) in leaves when targeted to the endoplasmic reticulum (ER) in transient expression assays. In this study the effects of ELP and HFBI fusion tags on recombinant protein accumulation levels and PB formation was examined in stable transgenic Nicotiana tabacum. RESULTS The accumulation of recombinant protein and PB formation was evaluated in two cultivars of Nicotiana tabacum transformed with green fluorescent protein (GFP) fused to ELP or HFBI, both targeted and retrieved to the ER. The ELP and HFBI tags increased the accumulation of the recombinant protein and induced the formation of PBs in leaves of stable transgenic plants from both cultivars. Furthermore, these tags induced the formation of PBs in a concentration-dependent manner, where a specific level of recombinant protein accumulation was required for PBs to appear. Moreover, agro-infiltration of plants accumulating low levels of recombinant protein with p19, a suppressor of post-transcriptional gene silencing (PTGS), increased accumulation levels in four independent transgenic lines, suggesting that PTGS might have caused the low accumulation levels in these plants. CONCLUSION The use of ELP and HFBI tags as fusion partners in stable transgenic plants of tobacco is feasible and promising. In a constitutive environment, these tags increase the accumulation levels of the recombinant protein and induce the formation of PBs regardless of the cultivar used. However, a specific level of recombinant protein accumulation needs to be reached for PBs to form.
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Affiliation(s)
- Sonia P Gutiérrez
- Department of Biology, University of Western Ontario, London, ON, Canada
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Reza Saberianfar
- Department of Biology, University of Western Ontario, London, ON, Canada
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Susanne E Kohalmi
- Department of Biology, University of Western Ontario, London, ON, Canada
| | - Rima Menassa
- Department of Biology, University of Western Ontario, London, ON, Canada
- Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
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Sadumpati V, Kalambur M, Vudem DR, Kirti PB, Khareedu VR. Transgenic indica rice lines, expressing Brassica juncea Nonexpressor of pathogenesis-related genes 1 (BjNPR1), exhibit enhanced resistance to major pathogens. J Biotechnol 2013; 166:114-21. [PMID: 23664883 DOI: 10.1016/j.jbiotec.2013.04.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 04/03/2013] [Accepted: 04/21/2013] [Indexed: 11/26/2022]
Abstract
Brassica juncea Nonexpressor of pathogenesis-related genes 1 (BjNPR1) has been introduced into commercial indica rice varieties by Agrobacterium-mediated genetic transformation. Transgenic rice plants were regenerated from the phosphinothricin-resistant calli obtained after co-cultivation with Agrobacterium strain LBA4404 harbouring Ti plasmid pSB111-bar-BjNPR1. Molecular analyses confirmed the stable integration and expression of BjNPR1 in various transgenic rice lines. Transgenes NPR1 and bar were stably inherited and disclosed co-segregation in subsequent generations in a Mendelian fashion. Homozygous transgenic rice lines expressing BjNPR1 protein displayed enhanced resistance to rice blast, sheath blight and bacterial leaf blight diseases. Rice transformants with higher levels of NPR1 revealed notable increases in plant height, panicle length, flag-leaf length, number of seeds/panicle and seed yield/plant as compared to the untransformed plants. The overall results amply demonstrate the profound impact of BjNPR1 in imparting resistance against major pathogens of rice. The multipotent BjNPR1, as such, seems promising as a prime candidate gene to fortify crop plants with durable resistance against various pathogens.
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Overexpression of the oil palm (Elaeis guineensis Jacq.) TAPETUM DEVELOPMENT1-like Eg707 in rice affects cell division and differentiation and reduces fertility. Mol Biol Rep 2012; 40:1579-90. [PMID: 23086301 DOI: 10.1007/s11033-012-2206-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 10/09/2012] [Indexed: 01/15/2023]
Abstract
The functional analysis of the TAPETUM DEVELOPMENT1-like analog Eg707 of oil palm was carried out in rice by over-expressing Eg707 under the control of a double cauliflower mosaic virus 35S promoter. Ectopic expression of Eg707 in rice induced dark green and matured compact brownish calli compared to pale wild type and negative control calli. Regenerated transgenic rice plants exhibited a reduction in organ size and plant height, rolled, erect leaves, less tillers, increased chlorophyll content, and reduced fertility with smaller green seeds. At the molecular level Eg707 overexpression caused an increase in the transcription of SAPK9, a SnRK2 protein kinase family member that is activated by ABA and hyperosmotic stress. Together, the results show that ectopic Eg707 expression influences cell division and differentiation, presumably via altered hormone homeostasis.
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Cao Y, Wu G, Wu Y, Nie S, Zhang L, Lu C. Characterization of the transgenic rice event TT51-1 and construction of a reference plasmid. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:8550-8559. [PMID: 21749035 DOI: 10.1021/jf201699s] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Transgenic rice TT51-1 (BT63) is an insect resistant strain that was granted for safety certificate in China in 2009. This study characterizes the transgenic event TT51-1 using a GenomeWalker strategy. The organization of the transgenes indicated that the transgenes on two plasmids, pFHBT1 and pGL2RC7, had been integrated at the same locus. The sequence of the event TT51-1 spanned 8725 bp, including a truncated Cry1Ab/Ac cassette, an intact Cry1Ab/Ac cassette, two Amp gene segments, and an Hph gene segment. The 5' and 3' plant flanking sequences were isolated and used to locate the transgenes to chromosome 10 in TT51-1. The isolated TT51-1 fragment and a fragment of the rice PLD gene were integrated into a plasmid vector, to create plasmid pK-TT51 as a calibrator for detecting rice containing TT51-1. Analysis of unknown samples indicated that the reference plasmid was a reliable alternative to TT51-1 genomic DNA.
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Affiliation(s)
- Yinglong Cao
- Key Laboratory of Oil Crop Biology of the Ministry of Agriculture, Oilcrops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
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Cunha NB, Murad AM, Cipriano TM, Araújo ACG, Aragão FJL, Leite A, Vianna GR, McPhee TR, Souza GHMF, Waters MJ, Rech EL. Expression of functional recombinant human growth hormone in transgenic soybean seeds. Transgenic Res 2011; 20:811-26. [PMID: 21069461 DOI: 10.1007/s11248-010-9460-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Accepted: 10/24/2010] [Indexed: 10/18/2022]
Abstract
We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, in genetically engineered soybean [Glycine max (L.) Merrill] seeds. Utilising the alpha prime (α') subunit of β-conglycinin tissue-specific promoter from soybean and the α-Coixin signal peptide from Coix lacryma-jobi, we obtained transgenic soybean lines that expressed the mature form of hGH in their seeds. Expression levels of bioactive hGH up to 2.9% of the total soluble seed protein content (corresponding to approximately 9 g kg(-1)) were measured in mature dry soybean seeds. The results of ultrastructural immunocytochemistry assays indicated that the recombinant hGH in seed cotyledonary cells was efficiently directed to protein storage vacuoles. Specific bioassays demonstrated that the hGH expressed in the soybean seeds was fully active. The recombinant hGH protein sequence was confirmed by mass spectrometry characterisation. These results demonstrate that the utilisation of tissue-specific regulatory sequences is an attractive and viable option for achieving high-yield production of recombinant proteins in stable transgenic soybean seeds.
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Affiliation(s)
- Nicolau B Cunha
- Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica (PqEB), Av. W5 Norte, Brasília, DF, 70770-917, Brazil
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Shukurov RR, Voblikova VD, Nikonorova AK, Egorov TA, Grishin EV, Babakov AV. Increase of resistance of Arabidopsis thaliana plants to phytopathogenic fungi expressing hevein-like peptides from weed plant Stellaria media. ACTA ACUST UNITED AC 2010. [DOI: 10.3103/s1068367410040117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Borejsza-Wysocka E, Norelli JL, Aldwinckle HS, Malnoy M. Stable expression and phenotypic impact of attacin E transgene in orchard grown apple trees over a 12 year period. BMC Biotechnol 2010; 10:41. [PMID: 20525262 PMCID: PMC2910661 DOI: 10.1186/1472-6750-10-41] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Accepted: 06/03/2010] [Indexed: 11/10/2022] Open
Abstract
Background Transgenic trees currently are being produced by Agrobacterium-mediated transformation and biolistics. The future use of transformed trees on a commercial basis depends upon thorough evaluation of the potential environmental and public health risk of the modified plants, transgene stability over a prolonged period of time and the effect of the gene on tree and fruit characteristics. We studied the stability of expression and the effect on resistance to the fire blight disease of the lytic protein gene, attacin E, in the apple cultivar 'Galaxy' grown in the field for 12 years. Results Using Southern and western blot analysis, we compared transgene copy number and observed stability of expression of this gene in the leaves and fruit in several transformed lines during a 12 year period. No silenced transgenic plant was detected. Also the expression of this gene resulted in an increase in resistance to fire blight throughout 12 years of orchard trial and did not affect fruit shape, size, acidity, firmness, weight or sugar level, tree morphology, leaf shape or flower morphology or color compared to the control. Conclusion Overall, these results suggest that transgene expression in perennial species, such as fruit trees, remains stable in time and space, over extended periods and in different organs. This report shows that it is possible to improve a desirable trait in apple, such as the resistance to a pathogen, through genetic engineering, without adverse alteration of fruit characteristics and tree shape.
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Peng Q, Hu Y, Wei R, Zhang Y, Guan C, Ruan Y, Liu C. Simultaneous silencing of FAD2 and FAE1 genes affects both oleic acid and erucic acid contents in Brassica napus seeds. PLANT CELL REPORTS 2010; 29:317-25. [PMID: 20130882 DOI: 10.1007/s00299-010-0823-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Revised: 01/11/2010] [Accepted: 01/12/2010] [Indexed: 05/18/2023]
Abstract
The fatty acid composition in the seed oil was significantly modified following the introduction of transgenes. To further enhance the desirable characteristics of rapeseed oil, it would be beneficial to develop a new approach for the simultaneous silencing of two or more target genes. Our goals in the current study were to (1) increase oleic acid to more than 75%, (2) reduce polyunsaturated fatty acids (PUFA) to about 10% and erucic acid to zero, and (3) accomplish these changes in a single-transformation event. In a single transformation, two fragments amplified from the fatty acid (Delta12)-desaturase 2 (BnaFAD2) and fatty acid elongase 1 (BnaFAE1) genes of Brassica napus were linked together to form a fusion fragment. The fusion fragment was then used to assemble unique intron-spliced hairpin interfering constructs. In the transgenic plant FFRP4-4, the expression of BnaFAD2 and BnaFAE1 genes was completely inhibited. The composition of oleic acid in FFRP4-4 rose to 85%, PUFA dropped to 10% and erucic acid was undetectable. All hybrid F(1) seeds obtained from the reciprocal crossing of FFRP4-4 and GX-parents (with different genetic backgrounds) contained more than 80% oleic acid, about 10% PUFA and very low, or undetectable, erucic acid. The results confirmed that the fusion fragment silencing construct can simultaneously and effectively silence the target genes on a consistent basis. The strategy provides a useful tool for detecting gene function and advancing genetic engineering techniques for the improvement of agricultural crops.
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Affiliation(s)
- Qi Peng
- Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Provincial Institute of Oil Crops, Hunan Agricultural University, Changsha 410128, China
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Desai PN, Shrivastava N, Padh H. Production of heterologous proteins in plants: strategies for optimal expression. Biotechnol Adv 2010; 28:427-35. [PMID: 20152894 DOI: 10.1016/j.biotechadv.2010.01.005] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 01/01/2010] [Accepted: 01/25/2010] [Indexed: 11/25/2022]
Abstract
Plants are a promising expression system for the production of heterologous proteins, especially therapeutic proteins. Currently the majority of therapeutic proteins are produced in mammalian cell lines or bacteria. In a few cases insects, yeast and fungi have been developed for production of human proteins. However, these expression systems have limitations in terms of suitability, cost, scalability, purification and post-translational modifications. Therefore, alternative expression systems are being developed in transgenic animals and transgenic plants. Transgenic plants could provide an attractive alternative in terms of low production cost and lower capital investment in infrastructure, and with appropriate post-translational modifications. The potential of plants as an expression host has not been capitalized, primarily due to lower level of expression of transgenes in plants. The present review will evaluate the rate limiting steps of plant expression systems and suggest strategies to optimize protein expression at each of the steps: gene integration, transcription, translation and protein accumulation.
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Affiliation(s)
- Priti N Desai
- B. V. Patel Pharmaceutical Education and Research Development Centre, Ahmedabad, India
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Choi HW, Yu XH, Lemaux PG, Cho MJ. Stability and inheritance of endosperm-specific expression of two transgenes in progeny from crossing independently transformed barley plants. PLANT CELL REPORTS 2009; 28:1265-1272. [PMID: 19529943 PMCID: PMC2717377 DOI: 10.1007/s00299-009-0726-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 05/11/2009] [Accepted: 05/27/2009] [Indexed: 05/27/2023]
Abstract
To study stability and inheritance of two different transgenes in barley, we crossed a homozygous T(8) plant, having uidA (or gus) driven by the barley endosperm-specific B(1)-hordein promoter (localized in the near centromeric region of chromosome 7H) with a second homozygous T(4) plant, having sgfp(S65T) driven by the barley endosperm-specific D-hordein promoter (localized on the subtelomeric region of chromosome 2H). Both lines stably expressed the two transgenes in the generations prior to the cross. Three independently crossed F(1) progeny were analyzed by PCR for both uidA and sgfp(S65T) in each plant and functional expression of GUS and GFP in F(2) seeds followed a 3:1 Mendelian segregation ratio and transgenes were localized by FISH to the same location as in the parental plants. FISH was used to screen F(2) plants for homozygosity of both transgenes; four homozygous plants were identified from the two crossed lines tested. FISH results showing presence of transgenes were consistent with segregation ratios of expression of both transgenes, indicating that the two transgenes were expressed without transgene silencing in homozygous progeny advanced to the F(3) and F(4) generations. Thus, even after crossing independently transformed, homozygous parental plants containing a single, stably expressed transgene, progeny were obtained that continued to express multiple transgenes through generation advance. Such stability of transgenes, following outcrossing, is an important attribute for trait modification and for gene flow studies.
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Affiliation(s)
- Hae-Woon Choi
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- School of Bioscience and Biotechnology, Chungnam National University, Daejeon, 305-764 Korea
| | - Xiao-Hong Yu
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- Biology Department, Brookhaven National Laboratory, 50 Bell Avenue, Upton, NY 11973 USA
| | - Peggy G. Lemaux
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
| | - Myeong-Je Cho
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720 USA
- RWC Research Campus, Pioneer Hi-Bred International, Inc., 700A Bay Road, Redwood City, CA 94063 USA
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Showalter AM, Heuberger S, Tabashnik BE, Carrière Y. A primer for using transgenic insecticidal cotton in developing countries. JOURNAL OF INSECT SCIENCE (ONLINE) 2009; 9:22. [PMID: 19613464 PMCID: PMC3011844 DOI: 10.1673/031.009.2201] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Accepted: 06/06/2008] [Indexed: 05/03/2023]
Abstract
Many developing countries face the decision of whether to approve the testing and commercial use of insecticidal transgenic cotton and the task of developing adequate regulations for its use. In this review, we outline concepts and provide information to assist farmers, regulators and scientists in making decisions concerning this technology. We address seven critical topics: 1) molecular and breeding techniques used for the development of transgenic cotton cultivars, 2) properties of transgenic cotton cultivars and their efficacy against major insect pests, 3) agronomic performance of transgenic cotton in developing countries, 4) factors affecting transgene expression, 5) impact of gene flow between transgenic and non-transgenic cotton, 6) non-target effects of transgenic cotton, and 7) management of pest resistance to transgenic cotton.
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Affiliation(s)
| | | | | | - Yves Carrière
- Department of Entomology, University of Arizona, Tucson AZ
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Yarasi B, Sadumpati V, Immanni CP, Vudem DR, Khareedu VR. Transgenic rice expressing Allium sativum leaf agglutinin (ASAL) exhibits high-level resistance against major sap-sucking pests. BMC PLANT BIOLOGY 2008; 8:102. [PMID: 18854007 PMCID: PMC2579298 DOI: 10.1186/1471-2229-8-102] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Accepted: 10/14/2008] [Indexed: 05/20/2023]
Abstract
BACKGROUND Rice (Oryza sativa) productivity is adversely impacted by numerous biotic and abiotic factors. An approximate 52% of the global production of rice is lost annually owing to the damage caused by biotic factors, of which approximately 21% is attributed to the attack of insect pests. In this paper we report the isolation, cloning and characterization of Allium sativum leaf agglutinin (asal) gene, and its expression in elite indica rice cultivars using Agrobacterium-mediated genetic transformation method. The stable transgenic lines, expressing ASAL, showed explicit resistance against major sap-sucking pests. RESULTS Allium sativum leaf lectin gene (asal), coding for mannose binding homodimeric protein (ASAL) from garlic plants, has been isolated and introduced into elite indica rice cultivars susceptible to sap-sucking insects, viz., brown planthopper (BPH), green leafhopper (GLH) and whitebacked planthopper (WBPH). Embryogenic calli of rice were co-cultivated with Agrobacterium harbouring pSB111 super-binary vector comprising garlic lectin gene asal along with the herbicide resistance gene bar, both under the control of CaMV35S promoter. PCR and Southern blot analyses confirmed stable integration of transgenes into the genomes of rice plants. Northern and western blot analyses revealed expression of ASAL in different transgenic rice lines. In primary transformants, the level of ASAL protein, as estimated by enzyme-linked immunosorbent assay, varied between 0.74% and 1.45% of the total soluble proteins. In planta insect bioassays on transgenic rice lines revealed potent entomotoxic effects of ASAL on BPH, GLH and WBPH insects, as evidenced by significant decreases in the survival, development and fecundity of the insects. CONCLUSION In planta insect bioassays were carried out on asal transgenic rice lines employing standard screening techniques followed in conventional breeding for selection of insect resistant plants. The ASAL expressing rice plants, bestowed with high entomotoxic effects, imparted appreciable resistance against three major sap-sucking insects. Our results amply demonstrate that transgenic indica rice harbouring asal exhibit surpassing resistance against BPH, GLH and WBPH insects. The prototypic asal transgenic rice lines appear promising for direct commercial cultivation besides serving as a potential genetic resource in recombination breeding.
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Affiliation(s)
- Bharathi Yarasi
- Centre for Plant Molecular Biology, Osmania University, Hyderabad, 500 007, India
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Sun HJ, Kataoka H, Yano M, Ezura H. Genetically stable expression of functional miraculin, a new type of alternative sweetener, in transgenic tomato plants. PLANT BIOTECHNOLOGY JOURNAL 2007; 5:768-77. [PMID: 17692073 DOI: 10.1111/j.1467-7652.2007.00283.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Miraculin is a taste-modifying protein isolated from the red berries of Richadella dulcifica, a shrub native to West Africa. Miraculin by itself is not sweet, but it is able to turn a sour taste into a sweet taste. This unique property has led to increasing interest in this protein. In this article, we report the high-yield production of miraculin in transgenic tomato plants. High and genetically stable expression of miraculin was confirmed by Western blot analysis and enzyme-linked immunosorbent assay. Recombinant miraculin accumulated to high levels in leaves and fruits, up to 102.5 and 90.7 microg/g fresh weight, respectively. Purified recombinant miraculin expressed in transgenic tomato plants showed strong sweetness-inducing activity, similar to that of native miraculin. These results demonstrate that recombinant miraculin was correctly processed in transgenic tomato plants, and that this production system could be a good alternative to production from the native plant.
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Affiliation(s)
- Hyeon-Jin Sun
- Graduate School of Life and Environmental Sciences, Gene Research Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan
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Yevtushenko DP, Misra S. Comparison of pathogen-induced expression and efficacy of two amphibian antimicrobial peptides, MsrA2 and temporin A, for engineering wide-spectrum disease resistance in tobacco. PLANT BIOTECHNOLOGY JOURNAL 2007; 5:720-34. [PMID: 17645440 DOI: 10.1111/j.1467-7652.2007.00277.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The rapid accumulation of defensive transgene products in plants only on pathogen invasion has clear advantages over their constitutive synthesis. In this study, two antimicrobial peptides from the skin secretions of frogs, MsrA2 (N-methionine-dermaseptin B1) and temporin A, were evaluated for engineering pathogen-induced disease resistance in plants. Both peptides inhibited plant-specific pathogens in vitro at micromolar concentrations that were not toxic to plant protoplasts. The plant-optimized nucleotide sequences encoding MsrA2 and temporin A were transcriptionally fused to the inducible win3.12T poplar promoter, which had strong systemic activity in response to fungal infection, and introduced into tobacco (Nicotiana tabacum L. cv. Xanthi). Transgene expression was very low in the leaves of unstressed plants; however, it was strongly increased after pathogen challenge or wounding. The pathogen responsiveness of the win3.12T promoter was found to be universal rather than species specific, with high activity in response to all pathogens tested. On induction, the amount of MsrA2 was up to 6-7 microg per gram of fresh leaf tissue. Most importantly, the induced accumulation of MsrA2 and temporin A in transgenic tobacco was sufficient to confer resistance to a variety of phytopathogenic fungi, such as Fusarium solani, F. oxysporum, Alternaria alternata, Botrytis cinerea, Sclerotinia sclerotiorum, the oomycete Pythium aphanidermatum and the bacterium Pectobacterium carotovorum. The accumulation of these peptides in transgenic plants did not alter the normal phenotype of tobacco. Thus, the expression of MsrA2 and temporin A in a pathogen-inducible manner enables the development of tobacco, and possibly other plant species, with wide-spectrum disease resistance, which can reduce the use of pesticides and the associated environmental risks.
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Affiliation(s)
- Dmytro P Yevtushenko
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 3P6, Canada
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Chiera JM, Bouchard RA, Dorsey SL, Park E, Buenrostro-Nava MT, Ling PP, Finer JJ. Isolation of two highly active soybean (Glycine max (L.) Merr.) promoters and their characterization using a new automated image collection and analysis system. PLANT CELL REPORTS 2007; 26:1501-9. [PMID: 17503049 DOI: 10.1007/s00299-007-0359-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2007] [Accepted: 03/31/2007] [Indexed: 05/15/2023]
Abstract
A novel automated image collection and analysis system was used to compare two new soybean (Glycine max (L.) Merr.) promoters with the cauliflower mosaic virus 35S (CaMV35S) promoter, which was used as an expression standard. For expression comparisons, various permutations of a soybean polyubiquitin (Gmubi) promoter, a soybean heat shock protein 90-like (GmHSP90L) promoter and the CaMV35S promoter were placed upstream of a green fluorescent protein (gfp) gene. DNA constructs were introduced via particle bombardment into excised cotyledons of germinating lima bean (Phaseolus lunatus L.) seeds, which were arranged in Petri dishes for automated image capture and image analysis. The automated system allowed monitoring and quantification of gfp gene expression in the same piece of tissue over time. The Gmubi promoter, with its intronic region intact, showed the highest expression that was over five times stronger than the CaMV35S promoter. When an intronic region was removed from the Gmubi promoter, GFP expression was reduced, but was still over two times greater than with the CaMV35S promoter. The full-length soybean GmHSP90L promoter was four times stronger than the CaMV35S promoter. Truncation of the GmHSP90L promoter resulted in stepwise decreases in promoter strength, which appear to correspond to removal of regulatory elements. Automated image capture and analysis allowed the rapid and efficient evaluation of these new promoters.
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Affiliation(s)
- Joseph M Chiera
- Department of Horticulture and Crop Science, OARDC/The Ohio State University, 1680 Madison Ave., Wooster, OH 44691, USA
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Maghuly F, da Câmara Machado A, Leopold S, Khan MA, Katinger H, Laimer M. Long-term stability of marker gene expression in Prunus subhirtella: A model fruit tree species. J Biotechnol 2007; 127:310-21. [PMID: 16889860 DOI: 10.1016/j.jbiotec.2006.06.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 06/14/2006] [Accepted: 06/23/2006] [Indexed: 11/22/2022]
Abstract
Transgenic trees currently are being produced by Agrobacterium-mediated transformation and biolistics. Since trees are particularly suited for long-term evaluations of the impact of the technology, Prunus subhirtella autumno rosa (PAR) was chosen as model fruit tree species and transformed with a reporter gene (uidA) under the control of the 35S promoter. Using Southern and GUS fluorometric techniques, we compared transgene copy numbers and observed stability of transgene expression levels in 34 different transgenic plants, grown under in vitro, greenhouse and screenhouse conditions, over a period of 9 years. An influence of grafting on gene expression was not observed. No silenced transgenic plant was detected. Overall, these results suggest that transgene expression in perennial species, such as fruit trees, remains stable in time and space, over extended periods and in different organs, confirming the value of PAR as model species to study season-dependent regulation in mature stone fruit tissues. While the Agrobacterium-derived Prunus transformants contained one to two copies of the transgenes, 91% of the transgenic events also contained various lengths of the bacterial plasmid backbone, indicating that the Agrobacterium-mediated transformation is not as precise as previously perceived. The implications for public acceptance and future applications are discussed.
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Affiliation(s)
- Fatemeh Maghuly
- Plant Biotechnology Unit, Institute of Applied Microbiology, Department of Biotechnology, BOKU, Nussdorfer Läende 11, A-1190 Vienna, Austria
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Sun HJ, Cui ML, Ma B, Ezura H. Functional expression of the taste-modifying protein, miraculin, in transgenic lettuce. FEBS Lett 2006; 580:620-6. [PMID: 16406368 DOI: 10.1016/j.febslet.2005.12.080] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2005] [Revised: 12/20/2005] [Accepted: 12/22/2005] [Indexed: 11/25/2022]
Abstract
Taste-modifying proteins are a natural alternative to artificial sweeteners and flavor enhancers and have been used in some cultures for centuries. The taste-modifying protein, miraculin, has the unusual property of being able to modify a sour taste into a sweet taste. Here, we report the use of a plant expression system for the production of miraculin. A synthetic gene encoding miraculin was placed under the control of constitutive promoters and transferred to lettuce. Expression of this gene in transgenic lettuce resulted in the accumulation of significant amounts of miraculin protein in the leaves. The miraculin expressed in transgenic lettuce possessed sweetness-inducing activity. These results demonstrate that the production of miraculin in edible plants can be a good alternative strategy to enhance the availability of this protein.
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Affiliation(s)
- Hyeon-Jin Sun
- Gene Research Center, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan
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Shiqing G, Huijun X, Xianguo C, Ming C, Zhaoshi X, Liancheng L, Xingguo Y, Lipu D, Xiaoyan H, Youzhi M. Improvement of wheat drought and salt tolerance by expression of a stress-inducible transcription factorGmDREB of soybean (Glycine max). CHINESE SCIENCE BULLETIN-CHINESE 2005. [DOI: 10.1007/bf02899641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Yevtushenko DP, Romero R, Forward BS, Hancock RE, Kay WW, Misra S. Pathogen-induced expression of a cecropin A-melittin antimicrobial peptide gene confers antifungal resistance in transgenic tobacco. JOURNAL OF EXPERIMENTAL BOTANY 2005; 56:1685-95. [PMID: 15863447 DOI: 10.1093/jxb/eri165] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Expression of defensive genes from a promoter that is specifically activated in response to pathogen invasion is highly desirable for engineering disease-resistant plants. A plant transformation vector was constructed with transcriptional fusion between the pathogen-responsive win3.12T promoter from poplar and the gene encoding the novel cecropin A-melittin hybrid peptide (CEMA) with strong antimicrobial activity. This promoter-transgene combination was evaluated in transgenic tobacco (Nicotiana tabacum L. cv. Xanthi) for enhanced plant resistance against a highly virulent pathogenic fungus Fusarium solani. Transgene expression in leaves was strongly increased after fungal infection or mechanical wounding, and the accumulation of CEMA transcripts was found to be systemic and positively correlated with the number of transgene insertions. A simple and efficient in vitro regeneration bioassay for preliminary screening of transgenic lines against pathogenic fungi was developed. CEMA had strong antifungal activity in vitro, inhibiting conidia germination at concentrations that were non-toxic to tobacco protoplasts. Most importantly, the expression level of the CEMA peptide in vivo, regulated by the win3.12T promoter, was sufficient to confer resistance against F. solani in transgenic tobacco. The antifungal resistance of plants with high CEMA expression was strong and reproducible. In addition, leaf tissue extracts from transgenic plants significantly reduced the number of fungal colonies arising from germinated conidia. Accumulation of CEMA peptide in transgenic tobacco had no deleterious effect on plant growth and development. This is the first report showing the application of a heterologous pathogen-inducible promoter to direct the expression of an antimicrobial peptide in plants, and the feasibility of this approach to provide disease resistance in tobacco and, possibly, other crops.
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Affiliation(s)
- Dmytro P Yevtushenko
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, V8W 3P6 Canada
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Bajaj S, Mohanty A. Recent advances in rice biotechnology--towards genetically superior transgenic rice. PLANT BIOTECHNOLOGY JOURNAL 2005; 3:275-307. [PMID: 17129312 DOI: 10.1111/j.1467-7652.2005.00130.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Rice biotechnology has made rapid advances since the first transgenic rice plants were produced 15 years ago. Over the past decade, this progress has resulted in the development of high frequency, routine and reproducible genetic transformation protocols for rice. This technology has been applied to produce rice plants that withstand several abiotic stresses, as well as to gain tolerance against various pests and diseases. In addition, quality improving and increased nutritional value traits have also been introduced into rice. Most of these gains were not possible through conventional breeding technologies. Transgenic rice system has been used to understand the process of transformation itself, the integration pattern of transgene as well as to modulate gene expression. Field trials of transgenic rice, especially insect-resistant rice, have recently been performed and several other studies that are prerequisite for safe release of transgenic crops have been initiated. New molecular improvisations such as inducible expression of transgene and selectable marker-free technology will help in producing superior transgenic product. It is also a step towards alleviating public concerns relating to issues of transgenic technology and to gain regulatory approval. Knowledge gained from rice can also be applied to improve other cereals. The completion of the rice genome sequencing together with a rich collection of full-length cDNA resources has opened up a plethora of opportunities, paving the way to integrate data from the large-scale projects to solve specific biological problems.
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Affiliation(s)
- Shavindra Bajaj
- Gene Technology, The Horticulture and Food Research Institute of New Zealand Limited (HortResearch) 120 Mt. Albert Road, Private Bag 92169, Auckland, New Zealand.
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Sunilkumar G, Campbell LM, Hossen M, Connell JP, Hernandez E, Reddy AS, Smith CW, Rathore KS. A comprehensive study of the use of a homologous promoter in antisense cotton lines exhibiting a high seed oleic acid phenotype. PLANT BIOTECHNOLOGY JOURNAL 2005; 3:319-30. [PMID: 17129314 DOI: 10.1111/j.1467-7652.2005.00126.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
As opposed to first-generation biotechnology products, such as pest-resistant crops and herbicide-resistant crops, second-generation products often utilize plant-derived, homologous or heterologous genes and/or promoters. In this study, we evaluated the ability of a promoter from a gene encoding a major storage protein in cottonseed to drive an antisense sequence of the cotton FAD2 gene to down-regulate the activity of Delta-12 desaturase enzyme in cottonseeds. The oleic acid level in the transgenic cottonseeds approximately doubled from the wild-type level of 15%, with a concomitant decrease in the level of linoleic acid. A more extensive study of one line revealed a higher degree of seed-to-seed variability in the transgenic phenotype. A thorough investigation was conducted to determine the impact of the use of a homologous promoter to drive a transgene on the activity of the endogenous promoter. The results showed that the use of the homologous alpha-globulin B promoter for transgenic purposes did not adversely affect the expression of alpha-globulin B storage protein in cottonseed. The results obtained in this investigation on the use of a homologous promoter and antisense technology will be useful in the design of strategies to alter biosynthetic pathways for nutritional quality improvements and for the production of heterologous proteins of commercial value in seeds.
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Affiliation(s)
- Ganesan Sunilkumar
- Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843, USA
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Çürük S, Çetiner S, Elman C, Xia X, Wang Y, Yeheskel A, Zilberstein L, Perl-Treves R, Watad AA, Gaba V. Transformation of Recalcitrant Melon (Cucumis meloL.) Cultivars is Facilitated by Wounding with Carborundum. Eng Life Sci 2005. [DOI: 10.1002/elsc.200520069] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ramesh S, Nagadhara D, Pasalu IC, Kumari AP, Sarma NP, Reddy VD, Rao KV. Development of stem borer resistant transgenic parental lines involved in the production of hybrid rice. J Biotechnol 2005; 111:131-41. [PMID: 15219400 DOI: 10.1016/j.jbiotec.2004.04.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 03/13/2004] [Accepted: 04/01/2004] [Indexed: 11/23/2022]
Abstract
Stem borer resistant transgenic parental lines, involved in hybrid rice, were produced by Agrobacterium-mediated gene transfer method. Two pSB111 super-binary vectors containing modified cry1Ab/cry1Ac genes driven by maize ubiquitin promoter, and herbicide resistance gene bar driven by cauliflower mosaic virus 35S promoter were, used in this study. Embryogenic calli after co-cultivation with Agrobacterium were selected on the medium containing phosphinothricin. Southern blot analyses of primary transformants revealed the stable integration of bar, cry1Ab and cry1Ac coding sequences into the genomes of three parental lines with a predominant single copy integration and without any rearrangement of T-DNA. T1 progeny plants disclosed a monogenic pattern (3:1) of transgene segregation as confirmed by molecular analyses. Furthermore, the co-segregation of bar and cry genes in T1 progenies suggested that the transgenes are integrated at a single site in the rice genome. In different primary transformants with alien inbuilt resistance, the levels of cry proteins varied between 0.03 and 0.13% of total soluble proteins. These transgenic lines expressing insecticidal proteins afforded substantial resistance against stem borers. This is the first report of its kind dealing with the introduction of Bacillus thuringiensis (Bt) cry genes into the elite parental lines involved in the development of hybrid rice.
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Affiliation(s)
- S Ramesh
- Centre for Plant Molecular Biology, Osmania University, Hyderabad 500 007, India
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James VA, Worland B, Snape JW, Vain P. Development of a standard operating procedure (SOP) for the precise quantification of transgene expression levels in rice plants. PHYSIOLOGIA PLANTARUM 2004; 120:650-656. [PMID: 15032827 DOI: 10.1111/j.0031-9317.2004.0276.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Variation in transgene expression levels can result from uncontrolled differences in experimental protocols. It is important to quantify and eliminate this unwanted variation as much as possible in order to attain precision in transgenic studies. Large-scale transgenic studies could, by their design, generate additional variation. The influence of different plant growth, sampling and analysis strategies in generating spurious variation in transgene expression level quantification in rice plant populations was assessed. The use of multiple independent plant phenotypic analyses (enzymatic assays in this study) was identified as the major source of spurious variation (doubling or tripling the variation). The quantification of transgene expression levels was also found to be significantly influenced by plant age, the choice of leaf sampled and leaf size. All of these factors reduced the precision of molecular genetic studies and generated artefactual results in transgenic studies. Identification of the sources of extraneous variation allowed the development of a new standard operating procedure (SOP) for rice, designed to control spurious variation. SOP allowed the influence of differences in growth period and independent phenotypic analyses to be minimized. The coefficient of variation in transgene expression levels, between and within genetically identical rice plants, was reduced to approximately 10 to 15% using SOP. Adoption of quality assurance (QA) criteria such as SOP is key to improving the reproducibility of transgenic studies.
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Affiliation(s)
- Victoria A. James
- John Innes Centre, Crop Genetics Department, Colney Lane, Norwich NR4 7UH, UK
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48
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Vain P, De Buyser J, Bui Trang V, Haicour R, Henry Y. Foreign gene delivery into monocotyledonous species. Biotechnol Adv 2003; 13:653-71. [PMID: 14536368 DOI: 10.1016/0734-9750(95)02009-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Monocotyledonous plants are generally more recalcitrant to genetic transformation than dicotyledonous species. The absence of reliable Agrobacterium-mediated transformation methods and the difficulties associated with the culture of monocotyledonous tissues in vitro are mainly responsible for this situation. Until recently, the genetic transformation of monocotyledons was essentially performed by direct transfer of DNA into regenerable protoplasts or intact cells cultured in vitro, via polyethylene glycol treatment, electroporation or particle bombardment. Since 1990, the use of particle gun technology has revolutionized the genetic engineering of monocotyledonous species, allowing transformation to be more independent of the in vitro culture requirements. Today, at least one genotype of each major monocotyledonous crop species, including cereals, can be genetically transformed.
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Affiliation(s)
- P Vain
- Institut de Biotechnologie des plantes, bat 630, URA CNRS 1128, Université Paris-Sud, 91405 Orsay, France
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Mason HS, Warzecha H, Mor T, Arntzen CJ. Edible plant vaccines: applications for prophylactic and therapeutic molecular medicine. Trends Mol Med 2002; 8:324-9. [PMID: 12114111 DOI: 10.1016/s1471-4914(02)02360-2] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The use of edible plants for the production and delivery of vaccine proteins could provide an economical alternative to fermentation systems. Genes encoding bacterial and viral antigens are faithfully expressed in edible tissues to form immunogenic proteins. Studies in animals and humans have shown that ingestion of transgenic plants containing vaccine proteins causes production of antigen-specific antibodies in serum and mucosal secretions. In general, the technology is limited by low expression levels for nuclear-integrated transgenes, but recent progress in plant organelle transformation shows promise for enhanced expression. The stability and immunogenicity of orally delivered antigens vary greatly, which necessitates further study on protein engineering to enhance mucosal delivery. These issues are discussed with regard to the further development of plant-based vaccine technology.
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Affiliation(s)
- Hugh S Mason
- Boyce Thompson Institute for Plant Research, Tower Road, Ithaca, NY 14853-1801, USA.
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Finnegan EJ. Epialleles - a source of random variation in times of stress. CURRENT OPINION IN PLANT BIOLOGY 2002; 5:101-6. [PMID: 11856603 DOI: 10.1016/s1369-5266(02)00233-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
With the advent of biotechnology, epigenetics has gained in respectability. Recently, focus has moved away from the problems caused by the epigenetic silencing of transgenes to the adaptive advantages offered by stochastic epigenetic variation. Epialleles can form in response to environmental and genomic stresses, including polyploidization. They may be important in acclimation to a range of environmental conditions and in stabilizing polyploid genomes.
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