• Horticultural Science & Technology
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• v.32 no.3
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• pp.375-381
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• 2014

Transgenic potato was generated to express recombinant 5 repeated ${\beta}$-amyloid ($A{\beta}$) peptides, potential antigens to be applied as a preventive accine for Alzheimer's disease using Agrobacterium mediated transformation. The $A{\beta}$ peptides were fused to the human IgG Fc fragment enhancing protein and KDEL, which is the endoplasmic reticulum (ER) retention signal ($5A{\beta}$-FcK). The $5A{\beta}$-FcK, was expressed under the control of the duplicated 35S promoter. PCR analysis confirmed the presence of the transgene in several transgenic potato lines. Southern blot analysis showed only a single gene copy number in transgenic line 22, whereas multiple gene copy numbers were shown for transgenic lines 31 and 44. Northern blot analysis showed that line 22 had stronger mRNA levels when compared to lines 31 and 44. Immunoblot analysis confirmed that the $5A{\beta}$-FcK protein was expressed in the transgenic potato plant. These results indicate that $5A{\beta}$ fused to Fc can be expressed in potato plants.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.143-148
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• 2005

The coat protein mediated resistance to potato virus Y is assessed here in transgenic potato plants (Solanum tuberosum L., cv Claustar). Therefore, the corresponding cDNA from tunisian isolate of the virus was cloned into Agrobacterium tumefaciens binary vector. The transgenic lines were subsequently analysed for the presence and expression of the transgene. The CP cDNA copy number was determined for kanamycin resistant plants. Three selected transgenic lines and their S1 progeny resulting from tuber germination showed a high protection level against the virus. These data appear to support the hypothesis that the virus resistance is mediated by the translated viral coat protein expressed in transgenic potato lines.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.337-343
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• 2008

We generated transgenic tomato plants with Arabidopsis thaliana $H^+$/cation exchanger gene (C4X4) by Agrobactrium-mediated transformation. We confirmed transgene copy number and transcription by Southern and Northern blot analyses. The intact CAX4-expressing tomato (Lycopersicon esculentum) fruits contained 63-71% more calcium ($Ca^{2+}$) than wild-type fruits. Moreover, ectopic expression of C4X4 in tomato fruits did not show any significant increase of the four kinds of metallic cations analyzed ($Mg^{2+}$, $Fe^{2+}$, $Mn^{2+}$, and $Cu^{2+})$. The C4X4-expressing tomato plants including their fruits did not show any morphological alternations during whole growth period. These results suggest the enhanced Ca-substrate specificity of CAX4 exchanger in tomato. Therefore, intact CAX4 exchanger can be a useful tool for $Ca^{2+}$ nutrient enrichment of tomato fruits with reduced accumulation of undesirable cations.

• Plant Biotechnology Reports
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• v.2 no.4
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• pp.227-231
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• 2008

D-class cyclins play important roles in controlling the cell cycle in development and in response to external signals by forming the regulatory subunit of cyclin-dependent kinase (CDK) complexes. To evaluate the effects of D-class cyclins in transgenic rice plants, Arabidopsis cyclin D2 gene (CycD2) was linked to the maize ubiquitin1 promoter (Ubi1) and introduced into rice by the Agrobacterium-mediated transformation method. Genomic deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and Western blot hybridizations of the Ubi1:-CycD2 plants revealed copy number of transgene and its increased expression in leaf and callus cells at messenger RNA (mRNA) and/or protein levels. The H1 kinase assay using the immunoprecipitates of protein extracts from the Ubi1:CycD2 plants and nontransgenic controls demonstrated that the introduced Arabidopsis CycD2 forms a functional CycD2/CDK complex with an unidentified CDK of rice. Shoot and root growth was enhanced in the Ubi1:CycD2 seedlings compared with nontransgenic controls, together, suggesting that Arabidopsis cyclin D2 interacts with a rice cyclin-dependent kinase, consequently enhancing seedling growth.

• Journal of Aquaculture
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• v.13 no.1
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• pp.21-27
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• 2000

The successful gene transfer and transient expression was demonstrated in olive flounder embryos using lipofected sperm. Olive flounder sperm interacted with foregn plasmid DNA encapsidated by positively charged liposome. The maximum plasmid copy number that associated with the sperm was 5 copies/sperm based on the examination of DNA blot assay. The foreign DNA was transferred into fertilized eggs without any adverse effect on fertilization and survival of embryos (P>0.05) and retained in embryos until at least 42 hours with successful expression. The maximal expression was detected in 18 hours after fertilization at 18$^{\cird}C$ and gradually decreased with development of embryo. Most of DNA transferred into embryos persisted extrachromosomally without significant sign of integration or replication.

• Journal of Plant Biotechnology
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• v.35 no.2
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• pp.101-108
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• 2008

The Agrobacterium-mediated transformation has been successfully used method to introduce foreign genes into some monocotyledonous as well as a large number of dicotyledonous plants genome, We developed transgenic Chinese cabbage plants with insect-resistance gene, modified CryIAc, by Agrobacterium-transformation and confirmed transgene copy number by Southern blot analysis. We confirmed that twenty-nine out of 46 transgenic Chinese cabbage plants have single copy of CryIAc. To obtain the sequences information on the transferred DNA (T-DNA) integration into plant genome, we analyzed left border (LB) flanking sequences by genome walking (GW) PCR method. Out of 46 transgenic Chinese cabbage plants examined, 37 carried the vector backbone sequences. This result indicates that the transfer of the vector backbone from the binary vectors resulted mainly from inefficient termination of LB site. Analysis of T-DNA LB flanking region of 9 transgenic Chinese cabbage plants without vector backbone revealed that all LB ends were not conserved and nucleotides up to 36bp from the LB cleavage site were deleted.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.347-354
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• 2007

Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in human health and the environment. Prior to GM plant release, applicants should provide the information on GM crops for approval. We carried out this study to provide the molecular data for risk assessment of the GM Chinese cabbage plants with insect-resistance gene, modified CryIAc, which we obtained by Agrobacterium-transformation. From the molecular analysis with GM Chinese cabbage, we confirmed the transgene copy number and stability, the expression of the transgene, and integration region sequences between the transgene and the Chinese cabbage genome. Based on the unique integration DNA sequences, we designed specific primer set to detect GM Chinese cabbage and set up the GM cabbage detection method by qualitative PCR analysis. Qualitative analysis with GM Chinese cabbage progenies analysis was revealed the same as the result of herbicide treatment. Our results provided the molecular data for risk assessment analysis of GM Chinese cabbage and demonstrated that the primer set proposed could be useful to detect GM Chinese cabbage.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.384-391
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• 2009

Previously, two events (H15 and B20) of transgenic pepper (Capsicum annuum L.) that enhanced resistance to Cucumber mosaic virus (CMV) by the introduction of CMV coat protein (CP) gene were constructed. Presently, a single copy number of the CP gene was revealed in H15 and B20 by Southern blot. To predict possible unintended effects due to transgene insertion in an endogenous gene, we carried out sequencing of the 5'-flanking region of the CP gene and a Blastbased search. The results revealed that insertion of the transgene into genes encoding putative proteins may occur in the H15 and B20 transgenic event. Mutiplex polymerase chain reaction (PCR) for simultaneous detection and identification of transgenic pepper was conducted with a set of nine primers. Both transgenic event were differentiated from non-transgenic event by the presence of 267 bp and 430 bp PCR products indicative of CP gene specific primer pairs and primer pairs targeting the CP gene and 35S promoter. H15 and B20 uniquely possessed a 390 bp and 596 bp PCR product, respectively. The presence of a 1115 bp product corresponding to intrinsic pepper actin gene confirmed the use of pepper DNA as the PCR template. The primer set and PCR conditions used presently may allow the accurate and simple identification of CMV resistant transgenic pepper.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.105-116
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• 2011

Transgenic zoysiagrass (Zoysia japonica Steud.) expressing the bar gene inserted in the plant genome has been generated previously through Agrobacterium tumefaciens-mediated transformation. The GM zoysiagrass (event: JG21) permits efficient management of weed control of widely cultivated zoysiagrass fields, reducing the frequency and cost of using various herbicides for weed control. Now we have carried out the environmental risk assessment of JG21 prior to applying to the governmental regulatory agency for the commercial release of the GM turf grass outside of test plots. The morphological phenotypes, molecular analysis, weediness and gene flow from each test plot of JG21 and wild-type zoysiagrasses have been evaluated by selectively analyzing environmental effects. There were no marked differences in morphological phenotypes between JG21 and wild-type grasses. The JG21 retained its stable integration in the host plant in T1 generation, exhibiting a 3:1 segregation ratio according to the Mendelian genetics. We confirmed the copy number (1) of JG21 by using Southern blot analysis, as the transgenic plants were tolerant to ammonium glufosinate throughout the culture period. From cross-fertilization and gene flow studies, we found a 9% cross-pollination rate at the center of JG21 field and 0% at distances over 3 m from the field. The JG21 and wild-type zoysiagrass plants are not considered "weed" because zoysiagrasses generally are not dominant and do not spread into weedy areas easily. We assessed the horizontal gene transfer (HGT) of the transgene DNA to soil microorganisms from JG21 and wild-type plants. The bar gene was not detected from the total genomic DNA extracted from each rhizosphere soil of GM and non-GM Zoysia grass fields. Through the monitoring of JG21 transgene's unintentional release into the environment, we found no evidence for either pollen mediated gene flow of zoysiagrass or seed dispersal from the test field within a 3 km radius of the natural habitat.

• Molecules and Cells
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• v.41 no.5
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• pp.413-422
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• 2018

Soybean transgenic plants with ectopically expressed AtABF3 were produced by Agrobacterium-mediated transformation and investigated the effects of AtABF3 expression on drought and salt tolerance. Stable Agrobacterium-mediated soybean transformation was carried based on the half-seed method (Paz et al. 2006). The integration of the transgene was confirmed from the genomic DNA of transformed soybean plants using PCR and the copy number of transgene was determined by Southern blotting using leaf samples from $T_2$ seedlings. In addition to genomic integration, the expression of the transgenes was analyzed by RT-PCR and most of the transgenic lines expressed the transgenes introduced. The chosen two transgenic lines (line #2 and #9) for further experiment showed the substantial drought stress tolerance by surviving even at the end of the 20-day of drought treatment. And the positive relationship between the levels of AtABF3 gene expression and drought-tolerance was confirmed by qRT-PCR and drought tolerance test. The stronger drought tolerance of transgenic lines seemed to be resulted from physiological changes. Transgenic lines #2 and #9 showed ion leakage at a significantly lower level (P < 0.01) than ${\underline{n}}on-{\underline{t}}ransgenic$ (NT) control. In addition, the chlorophyll contents of the leaves of transgenic lines were significantly higher (P < 0.01). The results indicated that their enhanced drought tolerance was due to the prevention of cell membrane damage and maintenance of chlorophyll content. Water loss by transpiration also slowly proceeded in transgenic plants. In microscopic observation, higher stomata closure was confirmed in transgenic lines. Especially, line #9 had 56% of completely closed stomata whereas only 16% were completely open. In subsequent salt tolerance test, the apparently enhanced salt tolerance of transgenic lines was measured in ion leakage rate and chlorophyll contents. Finally, the agronomic characteristics of ectopically expressed AtABF3 transgenic plants ($T_2$) compared to NT plants under regular watering (every 4 days) or low rate of watering condition (every 10 days) was investigated. When watered regularly, the plant height of drought-tolerant line (#9) was shorter than NT plants. However, under the drought condition, total seed weight of line #9 was significantly higher than in NT plants (P < 0.01). Moreover, the pods of NT plants showed severe withering, and most of the pods failed to set normal seeds. All the evidences in the study clearly suggested that overexpression of the AtABF3 gene conferred drought and salt tolerance in major crop soybean, especially under the growth condition of low watering.