• Journal of Embryo Transfer
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• v.14 no.1
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• pp.1-8
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• 1999

The efficiency of transgenic livestock animal production may be improved by early selection of transgenci preimplantation embryos. To examine the possibility of GFP gene as a non-invasive marker for the early screening of transgenic embryo, the GFP gene was microinjected into rabbit zygotes and the later stages of preimplantation embryos were examined for the expression of GFP. The presence of injected DNA was detected by PCR analysis and the expression of GFP was detected by observing green fluorescence in embryos under a fluorescent microscope. Out of 108 GFP gene-injected rabbit zygotes, seventy three(67.6%) were fluorescence-positive. When 11 fluroresecence-positive blastocysts were analyzed for the presence of GFP gene by PCR, 6(54.5%) were positive, and all of the 8 flrouescence-negative blastocysts were also negative by PCR. The results indicate that the screening of transgene in rabbit embryos by PCR analysis and GFP detection could be a promising method for the preselection of transgenic embryos.

• BMB Reports
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• v.39 no.1
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• pp.61-67
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• 2006

Molecular co-suppression phenomena are important to consider in transgene experiments. Embryogenic cells were obtained from immature cotyledons and engineered with two different gene constructs (pHV and pHVS) through particle bombardment. Both constructs contain a gene conferring resistance to hygromycin (hpt) as a selective marker and a modified glycinin (11S globulin) gene (V3-1) as a target. sGFP(S65T) as a reporter gene was, however, inserted into the flanking region of the V3-1 gene (pHVS). Fluorescence microscopic screening after the selection of hygromycin, identified clearly the expression of sGFP(S65T) in the transformed soybean embryos bombarded with the pHVS construct. Stable integration of the transgenes was confirmed by polymerase chain reaction (PCR) and Southern blot analysis. Seeds of transgenic plants obtained from the pHV construct frequently lacked an accumulation of endogenous glycinin, which is encoded by homologous genes to the target gene V3-1. Most of the transgenic plants expressing sGFP(S65T) showed highly accumulation of glycinin. The expression of sGFP(S65T) and V3-1 inherits into the next generations. sGFP(S65T) as a reporter gene may be useful to increase the transformation efficiency of transgenic soybean with avoiding gene co-suppression.

• Journal of Microbiology
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• v.42 no.4
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• pp.340-345
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• 2004

To investigate the co-expression and crystallization of a fusion gene between the Bacillus thuringiensis crystal protein and a foreign protein in B. thuringiensis, the expression of the Cry1Ac fused with green fluorescent protein (GFP) genes in a B. thuringiensis $Cry^-B$ strain was examined. The cry1Ac gene was cloned in the B. thuringiensis-E. coli shuttle vector, pHT3101, under the control of the native cry1Ac gene promoter, while the GFP gene was inserted into the XhoI site upstream of the proteolytic cleavage site, in the middle region of the crylAc gene (pProAc-GFP). The B. thuringiensis $Cry^-B$ strain carrying pProAc-GFP (ProAc-GFP/CB) did not produce any inclusion bodies. However, the transformed strain expressed fusion protein forms although the expression level was relatively low. Furthermore, an immu­noblot analysis using GFP and Cry1Ac antibodies showed that the fusion protein was not a single spe­cies, but rather multiple forms. In addition, the N-terminal fragment of Cry1Ac and a non-fused GFP were also found in the B. thuringiensis $Cry^-B$ strain after autolysis. The sporulated cells before autolysis and the spore-crystal mixture after autolysis of ProAc-GFP/CB exhibited insecticidal activities against Plutella xylostella larvae. Accordingly, the current results suggest that a fusion crystal protein produced by the transfomant, ProAc-GFP/CB, can be functionally expressed but easily degraded in B. thuring­iensis.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.296-304
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• 2008

The transient and rapid expression system of a foreign protein in planta is a very useful technique in biotechnology application. We have investigated optimum condition of Agrobacterium-infiltration technique in which expression level of foreign proteins were maximized without detrimental effects on plants using GFP and Cucumber mosaic virus 2b protein, which is known as an enhancer of gene expression and a suppressor of post-transcriptional gene silencing(PTGS). The optimum expression level of both RNA and protein of GFP with minimum leaf impairment was obtained at $OD_{600}$=0.2 of Agrobactrium inocula. The steady-state levels of GFP RNA and protein generally peaked at 3 and 7 days post-infiltration(dpi), respectively. In the presence of 2b, both the magnitude and duration of GFP expression was highly increased and we could detect GFP level until 17 dpi. On the other hands, the 2b-mediated higher accumulation of foreign proteins resulted in the repression of normal leaf growth, possibly due to the limitation of supply of energy or materials required for growth maintenance. Using this Agrobacterium-infiltration system with 2b and GFP, we tested a hypothesis for the threshold model of PTGS initiation. Four GFP transgenic lines of N. benthamiana, which shows different expression level of GFP were tested to determine the threshold level for PTGS initiation. Agrobacterium-infiltration of GFP into those GFP-transgenic plants resulted in the co-silencing of the transgenic GFP. It was found that very low concentration of Agrobacterium with GFP and GFP+2b($OD_{600}$=0.002-0.02) which could not phenotypically induce an additive GFP expression, was enough to trigger PTGS pathway in all GFP transgenic plants. This strongly indicates that each GFP-transgenic plant should be expressing the transgenic GFP at its own pre-determined level and there was no buffer zone of additive GFP-expression to the threshold. In other words, the PTGS seems to be immediately activated as a self-defensive mechanism if an internal balance of gene expression is broken.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.241-244
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• 2012

This study was performed to analyze the generational transmission and the expression of the foreign gene in the GFP transgenic chickens. The transmission rate and the expression of the GFP gene was investigated from the GFP transgenic rooster (G2) as the first founder to the ninth (G8). Analysis of GFP expression in hatched chickens was used the UV lamp. When GFP was expressed in the wings, bill and legs of a chick, the bird only was selected as a transgenic chick. The average transmission rate of the overall transgenic was 38~58%. These results showed that the transmission of the GFP gene in the transgenic chickens in accordance with the laws of Mendel's continues to the next generation without gene silencing.

• IMMUNE NETWORK
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• v.4 no.3
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• pp.190-197
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• 2004

Background: Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic synovial inflammation which leads to joint destruction. Gene therapy of RA targets the players of inflammation or articular destruction. However, viral vectors have safety problems and side effects, while non-viral vectors suffer from inefficient gene transfer and fast loss of gene expression. To overcome the limits of non-vial vectors, an EBV-based plasmid which is known to exert prolonged high level gene expression can be used. Methods: pEBVGFP, pEBVIL-10, and pEBVvIL-10 were constructed by cloning GFP, IL-10, and vIL-10 genes into an EBV-based plasmid, respectively. The pGFP was used as a control plasmid. Each constructs were lipofected into HIG-82 rabbit synoviocytes. The expression of GFP was monitored by FACS and confocal microscopy. IL-10 and vIL-10 expressions were measured by ELISA. Results: GFP expression 2 days after transfection was achieved in 33.2% of cells. GFP-expressing cells transfected with pGFP decreased rapidly from 4 days after transfection and disappeared completely by 11 days. Cells transfected with pEBVGFP began to decrease slowly from 4 days. But GFP expression was detected for over 35 days. In addition, HIG-82 cells transfected with pEBVIL-10 ($44.6{\pm}1.5ng/ml$) or pEBVvIL-10 ($51.0{\pm}5.7ng/ml$) secreted these cytokines at high levels. High level cytokine production by hygromycin selection was maintained at least for up to 26 days after transfection. Conclusion: These results suggest that the EBV-based plasmid has a potential to improve non-viral gene transfer system and may be applicable to treat RA without the drawbacks of viral vectors.

• Korean Journal of Plant Resources
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• v.21 no.4
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• pp.249-253
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• 2008

Since there is no report about more than one gene expression simultaneously in a single mitochondria, this report is very important to novel type of eukaryotic gene expression. In this study, investigated whether mitochondrial expressed gene and GFP that expression in mitochondria of plant expressed to mitochondria. Expression vector (pBin) containing AtBI-1 (mitochondrial expressed gene) and GFP driven by 35S promoter was bombarded by gene gun to leaves and cotyledon of tobacco. Regenerated shoot confirmed expression of AtBI-1 in mitochondria by GFP expression, PCR, and Southern analysis. Successful mitochondria of plant cell transformation in this report implies possible eukaryotic mitochondrial transformation including plants and animals, and moreover two or more gene expression which can be excellent applicable protocols to pharmaceutical field including antibody production.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1367-1372
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• 2000

The present study was conducted to evaluate the efficiency of transgenic rabbit production by DNA microinjection using EGFP (Enhanced Green Fluorescent Protein) gene. In this experiment EGFP coding sequences fused to CMV promoter were microinjected into rabbit one-cell embryos, and then GFP expression and gene integration were evaluated in preimplantation embryos and fetuses recovered on day 15 of pregnancy to determine efficiency of transgenic rabbit production. Effect of DNA concentration was also tested on development in vitro following microinjection and transgene integration in fetuses. Development of embryos in vitro was decreased by DNA microinjection, but the rates of pregnancy and implantation were not significantly affected by microinjection. As development progressed in vitro percentage of GFP expression in rabbit embryos was decreased, resulting GFP expression detected in 37.5% of blastocysts. The efficiencies for production of transgenic fetuses were 4.0% and 7.6%, respectively, when $10ng/{\mu}l$ and $20ng/{\mu}l$ of DNA concentration were microinjected. Transgenic fetuses were confirmed by GFP expression and PCR analysis of fetus genomic DNA. These results indicated that DNA microinjection itself damaged embryo development and DNA concentration affected the efficiency of transgenic rabbit production.

• Journal of fish pathology
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• v.16 no.2
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• pp.69-73
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• 2003

In this study, GFP reporter gene was transfected into a fibroblast cell line RTG-2 using a polycationic transfection reagent (Superfect) and showed a successful expression of GFP. The transfection efficiency by Superfect was compared to the commonly used transfection method, i.e. DNA-calcium phosphate coprecipitatlon. Transfection by Superfect was more effective than calcium phosphate coprecipltation method (frequency of cell expressing orr was 11.3% and 3.5%, respectively). The optimal expression of GFP and {\beta}-galactosidase was observed when $5-6\;{\mu}{\ell}$ of Superfect per ${\mu}g$ DNA was used for transfcction, 1:5-6 ratio between DNA(${\mu}g$) and Superfect ($\mu\ell$).

• Journal of fish pathology
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• v.33 no.2
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• pp.163-169
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• 2020

Snakehead rhabdovirus (SHRV) is different from other fish novirhabdoviruses such as viral hemorrhagic septicemia virus (VHSV), infectious hematopoietic necrosis virus (IHNV), and hirame rhabdovirus (HIRRV) in that it replicates at high temperatures. Therefore, the delivery of foreign proteins to fish living at high water temperature would be possible by using recombinant SHRVs. In the present study, to evaluate the possible use of SHRV as a vehicle for foreign proteins delivery, we generated a recombinant SHRV that contains an enhanced-GFP (eGFP) gene between nucleoprotein (N) and phosphoprotein (P) genes (rSHRV-A-eGFP), and another recombinant SHRV expressing two heterologous genes by inserting an eGFP gene between N and P genes, and mCherry gene between P and M genes (rSHRV-AeGFP-BmCherry). Epithelioma papulosum cyprini (EPC) cells infected with the recombinant SHRVs showed strong fluorescence(s), suggesting the possible availability of recombinant SHRVs for the development of combined vaccines by expressing multiple foreign antigens.