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Rustgi S, Naveed S, Windham J, Zhang H, Demirer GS. Plant biomacromolecule delivery methods in the 21st century. Front Genome Ed 2022; 4:1011934. [PMID: 36311974 PMCID: PMC9614364 DOI: 10.3389/fgeed.2022.1011934] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
Abstract
The 21st century witnessed a boom in plant genomics and gene characterization studies through RNA interference and site-directed mutagenesis. Specifically, the last 15 years marked a rapid increase in discovering and implementing different genome editing techniques. Methods to deliver gene editing reagents have also attempted to keep pace with the discovery and implementation of gene editing tools in plants. As a result, various transient/stable, quick/lengthy, expensive (requiring specialized equipment)/inexpensive, and versatile/specific (species, developmental stage, or tissue) methods were developed. A brief account of these methods with emphasis on recent developments is provided in this review article. Additionally, the strengths and limitations of each method are listed to allow the reader to select the most appropriate method for their specific studies. Finally, a perspective for future developments and needs in this research area is presented.
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Affiliation(s)
- Sachin Rustgi
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Center, Florence, SC, United States
| | - Salman Naveed
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Center, Florence, SC, United States
| | - Jonathan Windham
- Department of Plant and Environmental Sciences, School of Health Research, Clemson University Pee Dee Research and Education Center, Florence, SC, United States
| | - Huan Zhang
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China
| | - Gözde S. Demirer
- Department of Chemical Engineering, California Institute of Technology, Pasadena, CA, United States
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2
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Ali Z, Shami A, Sedeek K, Kamel R, Alhabsi A, Tehseen M, Hassan N, Butt H, Kababji A, Hamdan SM, Mahfouz MM. Fusion of the Cas9 endonuclease and the VirD2 relaxase facilitates homology-directed repair for precise genome engineering in rice. Commun Biol 2020. [PMID: 31974493 DOI: 10.1038/s42003-020-0768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Precise genome editing by systems such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) requires high-efficiency homology-directed repair (HDR). Different technologies have been developed to improve HDR but with limited success. Here, we generated a fusion between the Cas9 endonuclease and the Agrobacterium VirD2 relaxase (Cas9-VirD2). This chimeric protein combines the functions of Cas9, which produces targeted and specific DNA double-strand breaks (DSBs), and the VirD2 relaxase, which brings the repair template in close proximity to the DSBs, to facilitate HDR. We successfully employed our Cas9-VirD2 system for precise ACETOLACTATE SYNTHASE (OsALS) allele modification to generate herbicide-resistant rice (Oryza sativa) plants, CAROTENOID CLEAVAGE DIOXYGENASE-7 (OsCCD7) to engineer plant architecture, and generate in-frame fusions with the HA epitope at HISTONE DEACETYLASE (OsHDT) locus. The Cas9-VirD2 system expands our ability to improve agriculturally important traits in crops and opens new possibilities for precision genome engineering across diverse eukaryotic species.
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Affiliation(s)
- Zahir Ali
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Ashwag Shami
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
- College of Science, Biology Department, Kingdom of Saudi Arabia (KSA), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Khalid Sedeek
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Radwa Kamel
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Abdulrahman Alhabsi
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Muhammad Tehseen
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Norhan Hassan
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Haroon Butt
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Ahad Kababji
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Samir M Hamdan
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Magdy M Mahfouz
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
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3
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Ali Z, Shami A, Sedeek K, Kamel R, Alhabsi A, Tehseen M, Hassan N, Butt H, Kababji A, Hamdan SM, Mahfouz MM. Fusion of the Cas9 endonuclease and the VirD2 relaxase facilitates homology-directed repair for precise genome engineering in rice. Commun Biol 2020; 3:44. [PMID: 31974493 PMCID: PMC6978410 DOI: 10.1038/s42003-020-0768-9] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 12/31/2019] [Indexed: 12/20/2022] Open
Abstract
Precise genome editing by systems such as clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) requires high-efficiency homology-directed repair (HDR). Different technologies have been developed to improve HDR but with limited success. Here, we generated a fusion between the Cas9 endonuclease and the Agrobacterium VirD2 relaxase (Cas9-VirD2). This chimeric protein combines the functions of Cas9, which produces targeted and specific DNA double-strand breaks (DSBs), and the VirD2 relaxase, which brings the repair template in close proximity to the DSBs, to facilitate HDR. We successfully employed our Cas9-VirD2 system for precise ACETOLACTATE SYNTHASE (OsALS) allele modification to generate herbicide-resistant rice (Oryza sativa) plants, CAROTENOID CLEAVAGE DIOXYGENASE-7 (OsCCD7) to engineer plant architecture, and generate in-frame fusions with the HA epitope at HISTONE DEACETYLASE (OsHDT) locus. The Cas9-VirD2 system expands our ability to improve agriculturally important traits in crops and opens new possibilities for precision genome engineering across diverse eukaryotic species. Ali, Shami, Sedeek et al. generate a fusion between Cas9 and the VirD2 relaxase (Cas9-VirD2), which combines the functions of both proteins in producing targeted and specific double strand breaks and promoting homology-directed repair. They show the utility of their method by producing herbicide resistant rice.
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Affiliation(s)
- Zahir Ali
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Ashwag Shami
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.,College of Science, Biology Department, Kingdom of Saudi Arabia (KSA), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Khalid Sedeek
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Radwa Kamel
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Abdulrahman Alhabsi
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Muhammad Tehseen
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Norhan Hassan
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Haroon Butt
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Ahad Kababji
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Samir M Hamdan
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Magdy M Mahfouz
- Laboratory for Genome Engineering and Synthetic Biology, Division of Biological Sciences, 4700 King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
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McClure CD, Southall TD. Getting Down to Specifics: Profiling Gene Expression and Protein-DNA Interactions in a Cell Type-Specific Manner. ADVANCES IN GENETICS 2015; 91:103-151. [PMID: 26410031 PMCID: PMC4604662 DOI: 10.1016/bs.adgen.2015.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The majority of multicellular organisms are comprised of an extraordinary range of cell types, with different properties and gene expression profiles. Understanding what makes each cell type unique and how their individual characteristics are attributed are key questions for both developmental and neurobiologists alike. The brain is an excellent example of the cellular diversity expressed in the majority of eukaryotes. The mouse brain comprises of approximately 75 million neurons varying in morphology, electrophysiology, and preferences for synaptic partners. A powerful process in beginning to pick apart the mechanisms that specify individual characteristics of the cell, as well as their fate, is to profile gene expression patterns, chromatin states, and transcriptional networks in a cell type-specific manner, i.e., only profiling the cells of interest in a particular tissue. Depending on the organism, the questions being investigated, and the material available, certain cell type-specific profiling methods are more suitable than others. This chapter reviews the approaches presently available for selecting and isolating specific cell types and evaluates their key features.
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Affiliation(s)
- Colin D. McClure
- Department of Life Sciences, Imperial College London, Sir Ernst Chain Building, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Tony D. Southall
- Department of Life Sciences, Imperial College London, Sir Ernst Chain Building, South Kensington Campus, London SW7 2AZ, United Kingdom
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5
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Krishna G, Singh BK, Kim EK, Morya VK, Ramteke PW. Progress in genetic engineering of peanut (Arachis hypogaea L.)--a review. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:147-62. [PMID: 25626474 DOI: 10.1111/pbi.12339] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/27/2014] [Accepted: 12/17/2014] [Indexed: 05/20/2023]
Abstract
Peanut (Arachis hypogaea L.) is a major species of the family, Leguminosae, and economically important not only for vegetable oil but as a source of proteins, minerals and vitamins. It is widely grown in the semi-arid tropics and plays a role in the world agricultural economy. Peanut production and productivity is constrained by several biotic (insect pests and diseases) and abiotic (drought, salinity, water logging and temperature aberrations) stresses, as a result of which crop experiences serious economic losses. Genetic engineering techniques such as Agrobacterium tumefaciens and DNA-bombardment-mediated transformation are used as powerful tools to complement conventional breeding and expedite peanut improvement by the introduction of agronomically useful traits in high-yield background. Resistance to several fungal, virus and insect pest have been achieved through variety of approaches ranging from gene coding for cell wall component, pathogenesis-related proteins, oxalate oxidase, bacterial chloroperoxidase, coat proteins, RNA interference, crystal proteins etc. To develop transgenic plants withstanding major abiotic stresses, genes coding transcription factors for drought and salinity, cytokinin biosynthesis, nucleic acid processing, ion antiporter and human antiapoptotic have been used. Moreover, peanut has also been used in vaccine production for the control of several animal diseases. In addition to above, this study also presents a comprehensive account on the influence of some important factors on peanut genetic engineering. Future research thrusts not only suggest the use of different approaches for higher expression of transgene(s) but also provide a way forward for the improvement of crops.
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Affiliation(s)
- Gaurav Krishna
- Jacob School of Biotechnology & Bioengineering, Sam Higginbottom Institute of Agriculture, Technology & Sciences (Formerly Allahabad Agricultural Institute), Deemed University, Allahabad, Uttar Pradesh, India
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6
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Que Q, Elumalai S, Li X, Zhong H, Nalapalli S, Schweiner M, Fei X, Nuccio M, Kelliher T, Gu W, Chen Z, Chilton MDM. Maize transformation technology development for commercial event generation. FRONTIERS IN PLANT SCIENCE 2014; 5:379. [PMID: 25140170 PMCID: PMC4122164 DOI: 10.3389/fpls.2014.00379] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/17/2014] [Indexed: 05/22/2023]
Abstract
Maize is an important food and feed crop in many countries. It is also one of the most important target crops for the application of biotechnology. Currently, there are more biotech traits available on the market in maize than in any other crop. Generation of transgenic events is a crucial step in the development of biotech traits. For commercial applications, a high throughput transformation system producing a large number of high quality events in an elite genetic background is highly desirable. There has been tremendous progress in Agrobacterium-mediated maize transformation since the publication of the Ishida et al. (1996) paper and the technology has been widely adopted for transgenic event production by many labs around the world. We will review general efforts in establishing efficient maize transformation technologies useful for transgenic event production in trait research and development. The review will also discuss transformation systems used for generating commercial maize trait events currently on the market. As the number of traits is increasing steadily and two or more modes of action are used to control key pests, new tools are needed to efficiently transform vectors containing multiple trait genes. We will review general guidelines for assembling binary vectors for commercial transformation. Approaches to increase transformation efficiency and gene expression of large gene stack vectors will be discussed. Finally, recent studies of targeted genome modification and transgene insertion using different site-directed nuclease technologies will be reviewed.
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Affiliation(s)
- Qiudeng Que
- Syngenta Biotechnology, Inc.Research Triangle Park, NC, USA
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7
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D'Halluin K, Vanderstraeten C, Van Hulle J, Rosolowska J, Van Den Brande I, Pennewaert A, D'Hont K, Bossut M, Jantz D, Ruiter R, Broadhvest J. Targeted molecular trait stacking in cotton through targeted double-strand break induction. PLANT BIOTECHNOLOGY JOURNAL 2013; 11:933-41. [PMID: 23777410 PMCID: PMC4272417 DOI: 10.1111/pbi.12085] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 04/16/2013] [Accepted: 04/24/2013] [Indexed: 05/20/2023]
Abstract
Recent developments of tools for targeted genome modification have led to new concepts in how multiple traits can be combined. Targeted genome modification is based on the use of nucleases with tailor-made specificities to introduce a DNA double-strand break (DSB) at specific target loci. A re-engineered meganuclease was designed for specific cleavage of an endogenous target sequence adjacent to a transgenic insect control locus in cotton. The combination of targeted DNA cleavage and homologous recombination-mediated repair made precise targeted insertion of additional trait genes (hppd, epsps) feasible in cotton. Targeted insertion events were recovered at a frequency of about 2% of the independently transformed embryogenic callus lines. We further demonstrated that all trait genes were inherited as a single genetic unit, which will simplify future multiple-trait introgression.
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Affiliation(s)
- Kathleen D'Halluin
- Bayer CropScience N.V.Gent, Belgium
- * Correspondence (Tel +32 9 243 05 45; fax +32 9 383 67 31; email )
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8
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Ziemienowicz A, Shim YS, Matsuoka A, Eudes F, Kovalchuk I. A novel method of transgene delivery into triticale plants using the Agrobacterium transferred DNA-derived nano-complex. PLANT PHYSIOLOGY 2012; 158:1503-13. [PMID: 22291201 PMCID: PMC3320166 DOI: 10.1104/pp.111.192856] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 01/25/2012] [Indexed: 05/22/2023]
Abstract
Genetic transformation of monocotyledonous plants still presents a challenge for plant biologists and biotechnologists because monocots are difficult to transform with Agrobacterium tumefaciens, whereas other transgenesis methods, such as gold particle-mediated transformation, result in poor transgene expression because of integration of truncated DNA molecules. We developed a method of transgene delivery into monocots. This method relies on the use of an in vitro-prepared nano-complex consisting of transferred DNA, virulence protein D2, and recombination protein A delivered to triticale microspores with the help of a Tat2 cell-penetrating peptide. We showed that this approach allowed for single transgene copy integration events and prevented degradation of delivered DNA, thus leading to the integration of intact copies of the transgene into the genome of triticale plants. This resulted in transgene expression in all transgenic plants regenerated from microspores transfected with the full transferred DNA/protein complex. This approach can easily substitute the bombardment technique currently used for monocots and will be highly valuable for plant biology and biotechnology.
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Affiliation(s)
- Alicja Ziemienowicz
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada T1K 3M4.
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Enhanced single copy integration events in corn via particle bombardment using low quantities of DNA. Transgenic Res 2009; 18:831-40. [PMID: 19381853 DOI: 10.1007/s11248-009-9265-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 04/01/2009] [Indexed: 10/20/2022]
Abstract
Transgene copy number is an important criterion for determining the utility of transgenic events. Single copy integration events are highly desirable when the objective is to produce marker free plants through segregation or when it is necessary to introgress different transgenes into commercial cultivars from different transgenic events. In contrast multi-copy events are advocated by several authors for higher expression of the transgene. Till recently, it was thought that employment of the particle gun for transformation results in the production of a high proportion of multi-copy events often with complex integration pattern when compared to Agrobacterium-mediated transformation. However, it has been demonstrated that usage of cassette DNA for bombardment in place of whole plasmids would result in simple insertion pattern of the transgenes. While investigating the effect of varying the cassette DNA amount on stable transformation, the frequency of occurrence of low copy events was observed to increase when lower doses of cassette DNA was employed for bombardment. Large scale experimentation with rigorous statistical analysis performed to verify the above observations employing Helium gun and the Electric discharge gun for gene delivery confirmed the above observations. Helium gun experiments involving production of more than 1,600 corn events consistently yielded single copy events at higher frequencies at lower cassette DNA load (46% at 2.5 ng/shot) as compared to higher cassette DNA load (29% at 25 ng/shot) across 18 independent experiments. Results were nearly identical with the Electric discharge particle gun device where single copy events were recovered at frequencies of 54% at 2.5 ng cassettes DNA per shot as compared to 18% at 25 ng cassette DNA per shot. The transformation frequency declined from 41 to 34% (Helium gun) and from 48 to 31% (Electric discharge gun) with reduction in cassette DNA quantity from 25 to 2.5 ng per shot. This reduction in the transformation frequency is more than compensated by the savings in time and effort involved in the production and screening of events if the desired outcome is single copy events. These results demonstrate the flexibility of the particle gun method for controlling the frequency of production of either low copy or high copy events by altering the quantity of cassette DNA used for bombardment. The transgene expression levels over generations in relation to its integration need further investigations.
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D'Halluin K, Vanderstraeten C, Stals E, Cornelissen M, Ruiter R. Homologous recombination: a basis for targeted genome optimization in crop species such as maize. PLANT BIOTECHNOLOGY JOURNAL 2008; 6:93-102. [PMID: 17999657 DOI: 10.1111/j.1467-7652.2007.00305.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: 05/25/2023]
Abstract
In an attempt to understand the feasibility of future targeted genome optimization in agronomic crops, we tested the efficiency of homologous recombination-mediated sequence insertion upon induction of a targeted DNA double-strand break at the desired integration site in maize. By the development of an efficient tissue culture protocol, and with the use of an I-SceI gene optimized for expression in maize, large numbers of precisely engineered maize events were produced in which DNA integration occurred very accurately. In a subset of events examined in detail, no additional deletions and/or insertions of short filler DNA at the integration site were observed. In 30%-40% of the recovered events, no traces of random insertions were observed. This was true for DNA delivery by both Agrobacterium and particle bombardment. These data suggest that targeted double-strand break-induced homologous recombination is a superior method to generate specific desired changes in the maize genome, and suggest targeted genome optimization of agronomic crops to be feasible.
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Affiliation(s)
- Kathleen D'Halluin
- Bayer BioScience N.V., Technologiepark 38, B-9052 Gent, Belgium. kathleen.d'
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11
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De Buck S, Peck I, De Wilde C, Marjanac G, Nolf J, De Paepe A, Depicker A. Generation of single-copy T-DNA transformants in Arabidopsis by the CRE/loxP recombination-mediated resolution system. PLANT PHYSIOLOGY 2007; 145:1171-82. [PMID: 17693537 PMCID: PMC2151725 DOI: 10.1104/pp.107.104067] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We investigated whether complex T-DNA loci, often resulting in low transgene expression, can be resolved efficiently into single copies by CRE/loxP-mediated recombination. An SB-loxP T-DNA, containing two invertedly oriented loxP sequences located inside and immediately adjacent to the T-DNA border ends, was constructed. Regardless of the orientation and number of SB-loxP-derived T-DNAs integrated at one locus, recombination between the outermost loxP sequences in direct orientation should resolve multiple copies into a single T-DNA copy. Seven transformants with a complex SB-loxP locus were crossed with a CRE-expressing plant. In three hybrids, the complex T-DNA locus was reduced efficiently to a single-copy locus. Upon segregation of the CRE recombinase gene, only the simplified T-DNA locus was found in the progeny, demonstrating DNA had been excised efficiently in the progenitor cells of the gametes. In the two transformants with an inverted T-DNA repeat, the T-DNA resolution was accompanied by at least a 10-fold enhanced transgene expression. Therefore, the resolution of complex loci to a single-copy T-DNA insert by the CRE/loxP recombination system can become a valuable method for the production of elite transgenic Arabidopsis thaliana plants that are less prone to gene silencing.
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Affiliation(s)
- Sylvie De Buck
- Department of Plant Systems Biology, Flanders Institute for Biotechnology, and Department of Molecular Genetics, Ghent University, 9052 Gent, Belgium
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12
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Vengadesan G, Amutha S, Muruganantham M, Anand RP, Ganapathi A. Transgenic Acacia sinuata from Agrobacterium tumefaciens-mediated transformation of hypocotyls. PLANT CELL REPORTS 2006; 25:1174-80. [PMID: 16807750 DOI: 10.1007/s00299-006-0176-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 04/15/2006] [Accepted: 05/02/2006] [Indexed: 05/10/2023]
Abstract
Transgenic herbicide tolerant Acacia sinuata plants were produced by transformation with the bar gene conferring phosphinothricin resistance. Precultured hypocotyl explants were infected with Agrobacterium tumefaciens strain EHA105 in the presence of 100 microM acetosyringone and shoots regenerated on MS (Murashige and Skoog, 1962, Physiol Plant 15:473-497) medium with 13.3 microM benzylaminopurine, 2.6 microM indole-3-acetic acid, 1 g l(-1) activated charcoal, 1.5 mg l(-1) phosphinothricin, and 300 mg l(-1) cefotaxime. Phosphinothricin at 1.5 mg l(-1) was used for the selection. Shoots surviving selection on medium with phosphinothricin expressed GUS. Following Southern hybridization, eight independent shoots regenerated of 500 cocultivated explants were demonstrated to be transgenic, which represented transformation frequency of 1.6%. The transgenics carried one to four copies of the transgene. Transgenic shoots were propagated as microcuttings in MS medium with 6.6 microM 6-benzylaminopurine and 1.5 mg l(-1) phosphinothricin. Shoots elongated and rooted in MS medium with gibberellic acid and indole-3-butyric acid, respectively both supplemented with 1.5 mg l(-1) phosphinothricin. Micropropagation of transgenic plants by microcuttings proved to be a simple means to bulk up the material. Several transgenic plants were found to be resistant to leaf painting with the herbicide Basta.
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Affiliation(s)
- G Vengadesan
- Department of Biotechnology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, 620024, Tamilnadu, India.
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13
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Gao C, Jiang L, Folling M, Han L, Nielsen KK. Generation of large numbers of transgenic Kentucky bluegrass (Poa pratensis L.) plants following biolistic gene transfer. PLANT CELL REPORTS 2006; 25:19-25. [PMID: 16328388 DOI: 10.1007/s00299-005-0005-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 03/22/2005] [Accepted: 03/24/2005] [Indexed: 05/05/2023]
Abstract
A very efficient transformation system, using biolistic bombardment, has been developed for the production of transgenic plants of Kentucky bluegrass (Poa pratensis L.). Embryogenic calli, initiated from immature embryos, were transformed either with pAct1IHPT-4 containing the hygromycin phosphotransferase (hpt) gene or with pDM803 containing the phosphinothricin acetyltransferase (bar) gene and the beta-glucuronidase (uidA) gene. In total 119 independent transgenic plants were recovered from 153 hygromycin-resistant lines. Bialaphos selection yielded a total of 99 bialaphos-resistant lines and from these 34 independent transgenic plants were recovered. Southern blot analysis demonstrated the independent nature of the transgenic plants and also revealed a complex transgene integration pattern with multiple insertions.
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Affiliation(s)
- Caixia Gao
- DLF-Trifolium A/S, Research Division, Hoejerupvej 31, 4660 Store Heddinge, Denmark.
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14
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Travella S, Ross SM, Harden J, Everett C, Snape JW, Harwood WA. A comparison of transgenic barley lines produced by particle bombardment and Agrobacterium-mediated techniques. PLANT CELL REPORTS 2005; 23:780-9. [PMID: 15761662 DOI: 10.1007/s00299-004-0892-x] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Revised: 09/15/2004] [Accepted: 09/16/2004] [Indexed: 05/19/2023]
Abstract
Two barley transformation systems, Agrobacterium-mediated and particle bombardment, were compared in terms of transformation efficiency, transgene copy number, expression, inheritance and physical structure of the transgenic loci using fluorescence in situ hybridisation (FISH). The efficiency of Agrobacterium-mediated transformation was double that obtained with particle bombardment. While 100% of the Agrobacterium-derived lines integrated between one and three copies of the transgene, 60% of the transgenic lines derived by particle bombardment integrated more than eight copies of the transgene. In most of the Agrobacterium-derived lines, the integrated T-DNA was stable and inherited as a simple Mendelian trait. Transgene silencing was frequently observed in the T1 populations of the bombardment-derived lines. The FISH technique was able to reveal additional details of the transgene integration site. For the efficient production of transgenic barley plants, with stable transgene expression and reduced silencing, the Agrobacterium-mediated method appears to offer significant advantages over particle bombardment.
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Affiliation(s)
- S Travella
- John Innes Centre, Norwich Research Park, Colney, Norwich, NR4 7UH, UK
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15
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Taylor NJ, Fauquet CM. Microparticle bombardment as a tool in plant science and agricultural biotechnology. DNA Cell Biol 2002; 21:963-77. [PMID: 12573053 DOI: 10.1089/104454902762053891] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Microparticle bombardment technology has evolved as a method for delivering exogenous nucleic acids into plant cells and is a commonly employed technique in plant science. Desired genetic material is precipitated onto micron-sized metal particles and placed within one of a variety of devices designed to accelerate these "microcarriers" to velocities required to penetrate the plant cell wall. In this manner, transgenes can be delivered into the cell's genome or plastome. Since the late 1980s microparticle bombardment has become a powerful tool for the study of gene expression and production of stably transformed tissues and whole transgenic plants for experimental purposes and agricultural applications. This paper reviews development and application of the technology, including the protocols and mechanical systems employed as delivery systems, and the types of plant cells and culture systems employed to generate effective "targets" for receiving the incoming genetic material. Current understanding of how the exogenous DNA becomes integrated into the plant's native genetic background are assessed as are methods for improving the efficiency of this process. Pros and cons of particle bombardment technologies compared to alternative direct gene transfer methods and Agrobacterium based transformation systems are discussed.
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Affiliation(s)
- Nigel J Taylor
- International Laboratory for Tropical Agricultural Biotechnology, Danforth Plant Science Center, St. Louis, Missouri 63132, USA.
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Stahl R, Horvath H, Van Fleet J, Voetz M, von Wettstein D, Wolf N. T-DNA integration into the barley genome from single and double cassette vectors. Proc Natl Acad Sci U S A 2002; 99:2146-51. [PMID: 11854511 PMCID: PMC122333 DOI: 10.1073/pnas.032645299] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Patterns and sites of T-DNA integrations into the barley genome from single and double cassette vectors are of interest for the identification of cultivars with value added properties as well as for the production of selection marker-free transgenic lines that can be retransformed. T-DNA/Plant DNA junctions were obtained by capturing a single-stranded DNA with a biotinylated primer annealing to the vector adjacent to the border and an adaptor ligated to a restriction site overhang in the flanking barley DNA. The captured junction was converted into a double strand and sequenced. Fifty left and right border junctions from plants transgenic for one of five human genes were analyzed. Primers of 15-30 nucleotides designed from the genomic DNA at the insertion site can PCR amplify fragments that identify unequivocally any transformant. Adjacent transgene insertions with single cassette vectors were always in tandem direct repeat configuration. With regard to T-DNA integration the patterns were comparable to the variations found in dicotyledonous plants. Twelve of the 46 integrations characterized by blast searches were within different regions of the BARE-1 retrotransposon element occurring with a frequency of 2 x 10(5) copies in the barley genome. The use of border junctions to identify number of copies and loci of integrates in transformants is discussed.
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Affiliation(s)
- Rainer Stahl
- Maltagen Research Laboratory, Schaarstrasse 1, D-56626 Andernach, Germany
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17
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Lessard PA, Kulaveerasingam H, York GM, Strong A, Sinskey AJ. Manipulating gene expression for the metabolic engineering of plants. Metab Eng 2002; 4:67-79. [PMID: 11800576 DOI: 10.1006/mben.2001.0210] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Introducing and expressing foreign genes in plants present many technical challenges that are not encountered with microbial systems. This review addresses the variety of issues that must be considered and the variety of options that are available, in terms of choosing transformation systems and designing recombinant transgenes to ensure appropriate expression in plant cells. Tissue specificity and proper developmental regulation, as well as proper subcellular localization of products, must be dealt with for successful metabolic engineering in plants..
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Affiliation(s)
- Philip A Lessard
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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18
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Srivastava V, Ow DW. Single-copy primary transformants of maize obtained through the co-introduction of a recombinase-expressing construct. PLANT MOLECULAR BIOLOGY 2001; 46:561-566. [PMID: 11516149 DOI: 10.1023/a:1010646100261] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We describe a variation of the method to generate single-copy transgenic plants by recombinase-mediated resolution of multiple insertions. In this study, a transgene construct flanked by oppositely oriented lox sites was co-bombarded into maize cells along with a cre-expressing construct. From analysis of the regenerated plants, a high percentage of the primary transformants harbored a single copy of the introduced transgene, and among these, a majority also lacked the cre construct. We deduce that the expression of cre must have contributed to resolving concatemeric molecules either prior to or after DNA integration into the maize genome.
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Affiliation(s)
- V Srivastava
- Plant Gene Expression Center, USDA-ARS, Albany, CA 94710, USA
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19
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Koprek T, Rangel S, McElroy D, Louwerse JD, Williams-Carrier RE, Lemaux PG. Transposon-mediated single-copy gene delivery leads to increased transgene expression stability in barley. PLANT PHYSIOLOGY 2001; 125:1354-62. [PMID: 11244115 PMCID: PMC65614 DOI: 10.1104/pp.125.3.1354] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2000] [Revised: 12/17/2000] [Accepted: 12/20/2000] [Indexed: 05/19/2023]
Abstract
Instability of transgene expression in plants is often associated with complex multicopy patterns of transgene integration at the same locus, as well as position effects due to random integration. Based on maize transposable elements Activator (Ac) and Dissociation (Ds), we developed a method to generate large numbers of transgenic barley (Hordeum vulgare var Golden Promise) plants, each carrying a single transgene copy at different locations. Plants expressing Ac transposase (AcTPase) were crossed with plants containing one or more copies of bar, a selectable herbicide (Basta) resistance gene, located between inverted-repeat Ds ends (Ds-bar). F(1) plants were self-pollinated and the F(2) generation was analyzed to identify plants segregating for transposed Ds-bar elements. Of Ds-bar transpositions, 25% were in unlinked sites that segregated from vector sequences, other Ds-bar copies, and the AcTPase gene, resulting in numerous single-copy Ds-bar plants carrying the transgene at different locations. Transgene expression in F(2) plants with transposed Ds-bar was 100% stable, whereas only 23% of F(2) plants carrying Ds-bar at the original site expressed the transgene product stably. In F(3) and F(4) populations, transgene expression in 81.5% of plants from progeny of F(2) plants with single-copy, transposed Ds-bar remained completely stable. Analysis of the integration site in single-copy plants showed that transposed Ds-bar inserted into single- or low-copy regions of the genome, whereas silenced Ds-bar elements at their original location were inserted into redundant or highly repetitive genomic regions. Methylation of the non-transposed transgene and its promoter, as well as a higher condensation of the chromatin around the original integration site, was associated with plants exhibiting transgene silencing.
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Affiliation(s)
- T Koprek
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
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20
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Li W, Guo G, Zheng G. Agrobacterium-mediated transformation: state of the art and future prospect. ACTA ACUST UNITED AC 2000. [DOI: 10.1007/bf02886209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Mäenpää P, Gonzalez EB, Ahlandsberg S, Jansson C. Transformation of nuclear and plastomic plant genomes by biolistic particle bombardment. Mol Biotechnol 1999; 13:67-72. [PMID: 10934523 DOI: 10.1385/mb:13:1:67] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Microprojectile bombardment is a powerful method for the transformation of various organisms and tissues. For plants, the biolistic approach is primarily used for transformation of cereals and other monocotyledons, as well as for dicotyledonous plants shown to be recalcitrant to Agrobacterium-based transformation of organellar genomes, and transformation of plant and algal chloroplasts has recently been reported. In this protocol paper we provide methods for nuclear and plastomic transformation of plants using the biolistic technique.
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Affiliation(s)
- P Mäenpää
- Department of Biology, University of Turku, Finland.
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22
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Srivastava V, Anderson OD, Ow DW. Single-copy transgenic wheat generated through the resolution of complex integration patterns. Proc Natl Acad Sci U S A 1999; 96:11117-21. [PMID: 10500139 PMCID: PMC17996 DOI: 10.1073/pnas.96.20.11117] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/1999] [Indexed: 01/14/2023] Open
Abstract
Genetic transformation of plants often results in multiple copies of the introduced DNA at a single locus. To ensure that only a single copy of a foreign gene resides in the plant genome, we used a strategy based on site-specific recombination. The transformation vector consists of a transgene flanked by recombination sites in an inverted orientation. Regardless of the number of copies integrated between the outermost transgenes, recombination between the outermost sites resolves the integrated molecules into a single copy. An example of this strategy has been demonstrated with wheat transformation, where four of four multiple-copy loci were resolved successfully into single-copy transgenes.
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Affiliation(s)
- V Srivastava
- Plant Gene Expression Center, U.S. Department of Agriculture, Agricultural Research Service, Albany, CA 94710, USA
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23
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Affiliation(s)
- J J Finer
- Department of Horticulture and Crop Science, Ohio Agricultural Research and Development Center, Ohio State University, Wooster 44691, USA
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24
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Affiliation(s)
- G Hansen
- Novartis Agribusiness Biotechnology Research, Inc., Research Triangle Park, NC 27709, USA
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25
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Klein TM, Jones TJ. Methods of Genetic Transformation: The Gene Gun. MOLECULAR IMPROVEMENT OF CEREAL CROPS 1999. [DOI: 10.1007/978-94-011-4802-3_3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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26
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Methods of Genetic Transformation: Agrobacterium tumefaciens. MOLECULAR IMPROVEMENT OF CEREAL CROPS 1999. [DOI: 10.1007/978-94-011-4802-3_4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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27
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Relić B, Andjelković M, Rossi L, Nagamine Y, Hohn B. Interaction of the DNA modifying proteins VirD1 and VirD2 of Agrobacterium tumefaciens: analysis by subcellular localization in mammalian cells. Proc Natl Acad Sci U S A 1998; 95:9105-10. [PMID: 9689041 PMCID: PMC21299 DOI: 10.1073/pnas.95.16.9105] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Interaction between Agrobacterium tumefaciens and plants provides a unique example of interkingdom gene transfer. Agrobacterium, a plant pathogen, is capable to stably transform the plant cell with a segment of its own DNA called T-DNA (transferred DNA). This process depends, among others, on the specialized bacterial virulence proteins VirD1 and VirD2 that excise the T-DNA from its adjacent sequences. Subsequent to transfer to the plant cell, the virulence protein VirD2, through its nuclear localization signal (NLS), is believed to guide the T-DNA to the nucleus. The T-DNA then is integrated into the plant genome. Although both of these proteins are essential for bacterial virulence, physical interaction of them has not been analyzed so far. We studied associations between these proteins by expressing them in mammalian cells and by testing for intracellular localization and colocalization. When expressed in human cells [HeLa, human embryo kidney (HEK) 293], the VirD2 protein homogeneously distributed over the nucleoplasm. The presence of any of two NLSs, on the N and C termini of VirD2, was sufficient for its efficient nuclear localization whereas deletion of both NLSs rendered the protein cytoplasmic. However, this double NLS mutant was translocated to the nucleus in the presence of wild-type VirD2 protein, implying VirD2-VirD2 interaction. The VirD1 protein, by itself localized in the cytoplasm, moved to the nucleus when coexpressed with the VirD2 protein, suggesting VirD1-VirD2 interaction. This interaction was confirmed by coimmunoprecipitation tests. Of interest, both proteins coimported to the nucleus showed a similar, peculiar sublocalization. The data are discussed in terms of functions of the VirD proteins. In addition, coimport of proteins into nuclei is suggested as a useful system in studying individual protein-protein interactions.
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Affiliation(s)
- B Relić
- Friedrich Miescher-Institut, P.O. Box 2543, CH-4002 Basel, Switzerland.
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29
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Nelson DE, Shen B, Bohnert HJ. Salinity tolerance--mechanisms, models and the metabolic engineering of complex traits. GENETIC ENGINEERING 1998; 20:153-76. [PMID: 9666560 DOI: 10.1007/978-1-4899-1739-3_9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- D E Nelson
- Department of Biochemistry, University of Arizona, Tucson 85721-0088, USA
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30
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Affiliation(s)
- C I Kado
- Department of Plant Pathology, University of California, Davis 95616, USA
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31
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Abstract
Scientists have entered a new era of agricultural biotechnology. No longer is it sufficient merely to introduce a gene into a plant. The new generation of technology requires that genes be introduced into agronomically important crops in single copy and without the integration of extraneous vector 'backbone' sequences and, perhaps, even selectable markers. The expression of transgenes must be predictable and consistent among numerous independent transformants. Recent research has more clearly defined these problems and pointed the way to their solution.
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Affiliation(s)
- SB Gelvin
- Department of Biological Sciences Purdue University West Lafayette, IN 47907-1392, USA
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32
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Hansen G, Shillito RD, Chilton MD. T-strand integration in maize protoplasts after codelivery of a T-DNA substrate and virulence genes. Proc Natl Acad Sci U S A 1997; 94:11726-30. [PMID: 9326678 PMCID: PMC23615 DOI: 10.1073/pnas.94.21.11726] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/1997] [Indexed: 02/05/2023] Open
Abstract
We describe a plant protoplast transformation method that provides transformants with a simple pattern of integration of a foreign gene. The approach is to deliver into plant protoplasts by direct gene transfer the Agrobacterium virulence genes virD1 and virD2 with or without virE2, together with a target plasmid containing a gene of interest flanked by Agrobacterium T-DNA border repeat sequences of 25 bp. We present evidence of T-DNA formation in maize protoplasts and its integration into the maize genome. The frequency of VirD1-VirD2-mediated integration events was about 20-35% of the total number of transformants. The addition of virE2 doubled the transformation efficiency. The method described here is of sufficient efficiency and simplicity to be useful for the production of transgenic plants with single-copy well-defined transgenic inserts.
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Affiliation(s)
- G Hansen
- Novartis, P.O. Box 12257, Research Triangle Park, NC 27709, USA.
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