• Journal of Periodontal and Implant Science
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• v.32 no.3
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• pp.603-614
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• 2002

Human gingival fibroblasts have proven to useful as a species specific cell culture system in various system on periodontal disease and regeneration. However, their use is limited, since they are hard to obtain and lifespan is short due to replicative senescence. To overcome these disadvantages, we transfected primary human gingival fibroblasts by the E6 and E7 genes of the Human papilloma virus(HPV) 16. The full length of HPV 16 E6 and E7 was cloned from the pBR322 into BamHl and Sal I of a pBabe vector including hygromycin B resistance. Before pBabeE6/E7 plasmid transfection, peak 8 GFP including G418 resistance was transfected into primary GF to check the transfection efficency. PBabe E6/E7 plasmid was transfected using Lipofectamine plus following manufacter's instruction into primary normal human gingival fibroblasts in 60mm dishes with FBS free DMEM. After 2 days of transfection, the cells were treated with hygromycin for 2 weeks until the transfected control cells died. The resulting hygromycin resistant colonies were pooled, and clonned, and sucessful　transfection was established for immortalized gingival fibroblast cell lines. Immoralized GF cells showed stellate shape, that is similar to that of orange grains, and more rapid growth and higher proliferation than that of primary gingival fibroblasts. This cell lines overcame crisis and could be cultured over 30 subcultured, could be use for three dimentional culture, epithelial-mesenchymal interaction study.

• Korean Journal of Animal Reproduction
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• v.25 no.3
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• pp.277-286
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• 2001

Improvement and possible commercialization of a home-made electroporation apparatus(home-made) were further tried to establish a simple and effective introduction of foreign gene into sperm followed by in vitro fertilization. Expressions of introduced pJJ9 and pNT plasmids were shown in all fertilized eggs with electroporated spermatozoa. In particular, with this gene transfer system all the fry showed a consistently transient expression in the syncytium of the yolk sac. This fact is important since some required, minute quantity of human proteins can be produced from the established transient expression on the yolk sac of all fry derived from in vitro fertilization with electroporated spermatozoa. To explore tissue-specific expression in fish, which we will use a similar system later, we targeted the nerve tissue to see whether tissue-specific promoter is working in fish properly. pNT plasmid containing a nerve cell-specific tubulin promoter gene demonstrated consistently exact targeted expressions among the developing nerve cells in later stages of embryos and hatched fry. Finally, liver-specific genes are now being cloned by using already selected primers for useful human protein gene fusion.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.155-157
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• 2001

Bifidobacterium spp. is nonpathogenic, gram-positive and anaerobic bacteria, which inhabit the intestinal tract of humans and animals. In breast-fed infants, bifidobacteria comprise morethan 90％ of the gut bacterial population. Bifidobacteria spp. are used in commericial fermented dairy products and have been suggested to exert health promoting effects on the host by maintaining intestinal microflora balances, improving lactose tolerance, reducing serum cholesterol levels, increasing synthesis of vitamins, and aiding the immune enchancement and anticarcinogenic activity for the host. These beneficial effects of Bifidobacterium are strain-related. Therefore continued efforts to improve strain characteristics are warranted. in these respect, development of vector system for Bifidobacterium is very important not only for the strain improvement but also because Bifidobacterium is most promising in serving as a delivery system for the useful gene products, such as vaccine or anticarcinogenic polypeptides, into human intestinal tract. For developing vector system, we have characterized several bifidobacterial plasmids at genetic level and developed several shuttle vectors between E. coli and Bifidobacterium using them. Also, we have cloned and sequenced several metabolic genes and food grade selection marker. Also we have obtained bifidobacterial surface protein, which will be used as the mediator for surface display of foreign genes. Recently we have succeeded in expressing amylase and GFP in Bifidobacterium using our own expression vector system. Now we are in a very exciting stage for the molecular breeding and safe delivery system using probiotic Bifidobacterium strains.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.287-295
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• 2017

Water temperature is one of the major factors that impacts the growth and life cycle of Pyropia tenera, one of the most valuable and cultivated marine red algae belonging to Bangiales (Rhodophytes). We analyzed transcriptome from gametophyte of P. tenera under normal and high temperature conditions, and identified four small heat shock proteins (sHSPs). They have no significant amino acid sequence homology with known proteins in public databases except PhsHSP22 from Pyropia haitanensis. PtsHSP19.3 gene responded to high temperature but slightly or not to desiccation, freezing or high salt condition. When the PtsHSP19.3 gene was overexpressed in Chlamydomonas reinhardtii, transformed Chlamydomonas lines revealed much higher growth rate than that of control cells under heat stress condition. Transformed cells also grew well in those of the control cell onto the medium containing high salt or $H_2O_2$. When the PtsHSP19.3 was fused to GFP and introduced into tobacco protoplast, fluorescence was detected at several spots. Results indicate that PtsHSP19.3 may form super-molecular assembles and be involved in tolerance to heat stress.

• Korean Journal of Pharmacognosy
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• v.49 no.1
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• pp.40-46
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• 2018

Chaenomeles sinensis (Thouin) Koehne fruit (Rosaceae) has been used as a traditional medicine in Korea, Japan and China to treat sore throat, diarrhea and inflammation. The ethanol extract of C. sinensis fruit was successively partitioned as methylene chloride, ethyl acetate, n-butanol and $H_2O$ soluble fractions. Among those fractions, the n-butanol fraction showed the most potent DPPH radical scavenging and superoxide quenching activities. To verify antioxidant activities, the n-butanol fraction was checked the activities of superoxide dismutase (SOD) and catalase activities, and intracellular ROS levels and oxidative stress tolerance in Caenorhabditis elegans. Furthermore, to see if increased stress tolerance of worms by treating of the n-butanol fraction was due to regulation of stress-response gene, we quantified SOD-3 expression using transgenic strain. Consequently, the n-butanol fraction elevated SOD and catalase activities of C. elegans, and reduced intracellular ROS accumulation in a dose-dependent manner. Moreover, the n-butanol fraction-treated CF1553 worms exhibited significantly higher SOD-3::GFP intensity.

• Molecules and Cells
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• v.21 no.3
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• pp.418-427
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• 2006

Ionotropic glutamate receptors (iGluRs) are ligand-gated nonselective cation channels that mediate fast excitatory neurotransmission. Although homologues of the iGluRs have been identified in higher plants, their roles are largely unknown. In this work we isolated a full-length cDNA clone (RsGluR) encoding a putative glutamate receptor from small radish. An RsGluR:mGFP fusion protein was localized to the plasma membrane. In Arabidopsis thaliana overexpressing the fulllength cDNA, glutamate treatment triggered greater $Ca^{2+}$ influx in the root cells of transgenic seedlings than in those of the wild type. Transgenic plants exhibited multiple morphological changes such as necrosis at their tips and the margins of developing leaves, dwarf stature with multiple secondary inflorescences, and retarded growth, as previously observed in transgenic Arabidopsis overexpressing AtGluR3.2 [Kim et al. (2001)]. Microarray analysis showed that jasmonic acid (JA)-responsive genes including defensins and JA-biosynthetic genes were up-regulated. RsGluR overexpression also inhibited growth of a necrotic fungal pathogen Botrytis cinerea possibly due to up-regulation of the defensins. Based on these results, we suggest that RsGluR is a glutamate-gated $Ca^{2+}$ channel located in the plasma membrane of higher plants and plays a direct or indirect role in defense against pathogen infection by triggering JA biosynthesis.

• Molecules and Cells
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• v.28 no.2
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• pp.93-98
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• 2009

A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.

• Molecules and Cells
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• v.28 no.1
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• pp.43-48
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• 2009

By screening C. elegans mutants for severe defects in germline proliferation, we isolated a new loss-of-function allele of cdc-25.1, bn115. bn115 and another previously identified loss-of-function allele nr2036 do not exhibit noticeable cell division defects in the somatic tissues but have reduced numbers of germ cells and are sterile, indicating that cdc-25.1 functions predominantly in the germ line during postembryonic development, and that cdc-25.1 activity is probably not required in somatic lineages during larval development. We analyzed cell division of germ cells and somatic tissues in bn115 homozygotes with germline-specific anti-PGL-1 immunofluorescence and GFP transgenes that express in intestinal cells, in distal tip cells, and in gonadal sheath cells, respectively. We also analyzed the expression pattern of cdc-25.1 with conventional and quantitative RT-PCR. In the presence of three other family members of cdc-25.1 in C. elegans, defects are observed only in the germ line but not in the somatic tissues in cdc-25.1 single mutants, and cdc-25.1 is expressed predominantly, if not exclusively, in the germ line during postembryonic stages. Our findings indicate that the function of cdc-25.1 is unique in the germ line but likely redundant with other members in the soma.

• Korean Journal of Pharmacognosy
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• v.48 no.4
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• pp.298-303
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• 2017

To know the anti-oxidative effect of Epimedii Herba (Berberidaceae), the methanol extract of this plant was investigated by using a Caenorhabditis elegans model system. The methanol extract of this plant showed relatively significant DPPH radical scavenging and superoxide quenching activities. The ethyl acetate soluble fraction of Epimedii Herba (EHE), which showed the most potent DPPH radical scavenging and superoxide quenching activities, was tested on its effects on superoxide dismutase (SOD), catalase, intracellular ROS, and oxidative stress tolerance in Caenorhabditis elegans. Furthermore, in order to verify that regulation of stress-response genes is responsible for the increased stress tolerance of the EHE treated C. elegans, we checked SOD-3 expression using a transgenic strain. As a result, the EHE increased SOD and catalase activities of C. elegans, and reduced intracellular ROS accumulation in a dose-dependent manner. Besides, EHE-treated CF1553 worms showed higher SOD-3::GFP intensity than that of non-treated controls.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.17-30
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• 2013

Barley stripe mosaic virus (BSMV) induces massive actin filament thickening at the infection front of infected Nicotiana benthamiana leaves. To determine the mechanisms leading to actin remodeling, fluorescent protein fusions of the BSMV triple gene block (TGB) proteins were coexpressed in cells with the actin marker DsRed: Talin. TGB ectopic expression experiments revealed that TGB3 is a major elicitor of filament thickening, that TGB2 resulted in formation of intermediate DsRed:Talin filaments, and that TGB1 alone had no obvious effects on actin filament structure. Latrunculin B (LatB) treat-ments retarded BSMV cell-to-cell movement, disrupted actin filament organization, and dramatically decreased the proportion of paired TGB3 foci appearing at the cell wall (CW). BSMV infection of transgenic plants tagged with GFP-KDEL exhibited membrane proliferation and vesicle formation that were especially evident around the nucleus. Similar membrane proliferation occurred in plants expressing TGB2 and/or TGB3, and DsRed: Talin fluorescence in these plants colocalized with the ER vesicles. TGB3 also associated with the Golgi apparatus and overlapped with cortical vesicles appearing at the cell periphery. Brefeldin A treatments disrupted Golgi and also altered vesicles at the CW, but failed to interfere with TGB CW localization. Our results indicate that actin cytoskeleton interactions are important in BSMV cell-to-cell movement and for CW localization of TGB3.