• YAKHAK HOEJI
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• v.41 no.1
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• pp.94-98
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• 1997

Ceramide. a product of sphingomyelin hydrolysis, has been proposed as a lipid second messenger mediating antiproliferative activation. In this study, we examined the role of the cell cycle-related proteins in the ceramide-mediated growth suppression. Treatment of U-937 cells with C$_2$-ceramide(N-acetylsphingosine) resulted in growth suppression in a time- and concentration dependent manner. Ceramide induced concentration dependent dephosphorylation of retinoblastoma gene product (Rb). Rb remains hypophosphorylated in synchronized cells even after serum stimulation in the presence of ceramide. Ceramide decreased the expression of cyclin D$_1$ and cyclin E levels. These results suggest that antiproliferative effect of ceramide is associated with hypophosphorylation of Rb and decreased expression of cyclin D1 and cyclin E.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.3
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• pp.135-149
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• 2006

Purpose : This study was aimed to investigate the inhibitory effect of Millettia Reticulatas on the proliferation of human uterine leiomyoma cells and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of death cells treated with indicated concentration of Millettia Reticulatas and investigated cell death rate by MTS assay. Furthermore, flow cytometry analyis and DNA fragmentation assay were used to dissect between necrosis and apoptosis. and then we observed the differential gene expression by western blot analysis. Results : 1) The inhibitory effect on the growth of uterine leiomyoma cell treated with Millettia Reticulatas was increased in a concentration proportional. 2) The result of flow cytometry analysis. subG1 phase arrest related3 cell apoptosis was investigated 23.49% in uterine leiomyoma cell treated Millettia Reticulatas and showed the fession of proportional concentration. 3) The gene expression of p27, p53, p21, p16 related cell cycle was increased according to increasing concentration but cyclin E was none exchanged. 4) The character of apoptosis, DNA fragmentation was significantly observed the fession of proportional concentration. 5) The expression of pro-caspase3 and PARP were decreased dependent on treatment concentration. Conclusion : This study showed that Millettia Reticulatas have the inhibitory effect on the proliferation of human uterine leiomyoma cell and the effect was related with apoptosis. The apoptotic mechanism was observed that the gene expression of p27, p53, p21, p16 related cell cycle was increased according to increasing treatment concentration, induced G1 phase arrest and finally cell death was occurred. The decreased expression of pro-caspase 3 and PARP were noted that apoptosis was related with caspase pathway.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.387-392
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• 1998

Brevibacterium lactofermentum, a gram-positive bacteria, has both the diaminopimelate (DAP) pathway and meso-DAP-dehydrogenase (DDH) pathway for L-lysine biosynthesis. To investigate importance of DDH pathway and the related ddh gene in lysine production, we introduced site-specific mutagenesis technique. A 300 bp DNA fragment central to the meso-DAP-dehydrogenase gene (ddh) of B. lactofermentum was used to inactive chromosomal ddh gene via homologous recombination. Southern hybridization analysis confirmed that the chromosomal ddh gene was disrupted by the vector sequence. The B. lactofementum ddh mutant obtained have an inactive DDH pathway. The results reveal that inactivation of the ddh gene in B. lactofermentum leads to dramatic reduction of lysine production as well as decrease of the growth rate, indicating that the DDH pathway is essential for high-level lysine production as well as biosynthesis of meso-DAP.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.676-686
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• 2013

Background To overcome the potential drawbacks of a short half-life and dose-related adverse effects of using active transforming growth factor-beta 1 for cartilage engineering, a cell-mediated latent growth factor activation strategy was developed incorporating latent transforming growth factor-${\beta}$1 (LTGF) into an electrospun poly(L-lactide) scaffold. Methods The electrospun scaffold was surface modified with NH3 plasma and biofunctionalised with LTGF to produce both random and orientated biofunctionalised electrospun scaffolds. Scaffold surface chemical analysis and growth factor bioavailability assays were performed. In vitro biocompatibility and human nasal chondrocyte gene expression with these biofunctionalised electrospun scaffold templates were assessed. In vivo chondrogenic activity and chondrocyte gene expression were evaluated in athymic rats. Results Chemical analysis demonstrated that LTGF anchored to the scaffolds was available for enzymatic, chemical and cell activation. The biofunctionalised scaffolds were non-toxic. Gene expression suggested chondrocyte re-differentiation after 14 days in culture. By 6 weeks, the implanted biofunctionalised scaffolds had induced highly passaged chondrocytes to re-express Col2A1 and produce type II collagen. Conclusions We have demonstrated a proof of concept for cell-mediated activation of anchored growth factors using a novel biofunctionalised scaffold in cartilage engineering. This presents a platform for development of protein delivery systems and for tissue engineering.

• The Plant Pathology Journal
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• v.18 no.2
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• pp.57-62
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• 2002

In vivo expression technology (IVET) has been developed to study bacterial gene expression in Salmonella typhimurium during host infection. The expression of selected genes by IVET has been elevated in vivo but not in vitro. The selected genes turned out to be important for bacterial virulence and/or pathogenicity. IVET depends on a synthetic operon with a promoterless transcriptional fusion between a selection marker gene and a reporter gene. The IVET approach has been successfully adapted in other bacterial pathogens and plant-associated bacteria using different selection markers. Pseudomonas putida suppresses citrus root rot caused by Phytophthora parasitica and enhances citrus seedling growth. The WET strategy was adapted based on a transcriptional fusion, pyrBC'-lacZ, in P. putida to study the bacterial traits important far biocontrol activities. Several genes appeared to be induced on P. parasitica hyphae and were found to be related with metabolism and regulation of gene expression. It is likely that the biocontrol strain took a metabolic advantage from the plant pathogenic fungus and then suppressed citrus root rot effectively. The result was parallel with those from the adaptation of IVET in P. fluorescens, a plant growth promoting rhizobacteria (PGPR). Interestingly, genes encoding components for type III secretion system have been identified as rhizosphere-induced genes in the PGPR strain. The type III secretion system may play a certain role during interaction with its counterpart plants. Application of IVET has been demonstrated in a wide range of bacteria. It is an important strategy to genetically understand complicated bacterial traits in the environment.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.278-285
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• 1998

Effects of chitosan on growth of tomato plant, and suppression of Fusaruim wilt caused by Fusarium oxysporum f. sp. lycopersici and late blight casued by Phytophthora infestans, were examined. Both late blight and fusarium wilt were suppressed by spray and irrigation of chitosan, respectively. Inhibition of mycelial growth was not greatly affected by molecular size of chitosan but, concentration dependent effects was observed. Ninty percent of P. infestans and 80% of F. oxysporum f. sp. lycopersici of mycelial growth was inhibited by 1,000 ppm of chitosan (MW 30,000~50,000) when amended in plate media. Induction of defense-related gene expression in plant by chitosan treatments were observed when chitosan treated tobacco and tomato RNA samples were hybridized with several defense-related genes as probes. The results revealed that $\beta$-1,3-glucanase and chitinase genes were strongly induced, while pathogenesis-related protein-1, 3-hydroxy-3-methylglutaryl coenzyme A reductase, anionic peroxidase, phenylalanine ammonia lyase genes were weakly induced by chitosan treatment. These results suggest that chitosan have dual effects on these host-pathogen interactions. Possible roles of chitosan in suppression of tomato diseases by inhibition of mycelial growth and activation of plant defense responses are discussed.

• Mycobiology
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• v.46 no.2
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• pp.147-153
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• 2018

Certain beneficial microorganisms isolated from rhizosphere soil promote plant growth and induce resistance to a wide variety of plant pathogens. We obtained 49 fungal isolates from the rhizosphere soil of paprika plants, and selected 18 of these isolates that did not inhibit tomato seed germination for further investigation. Based on a seed germination assay, we selected four isolates for further plant tests. Treatment of seeds with isolate JF27 promoted plant growth in pot tests, and suppressed bacterial speck disease caused by Pseudomonas syringae pathovar (pv.) tomato DC3000. Furthermore, expression of the pathogenesis-related 1 (PR1) gene was higher in the leaves of tomato plants grown from seeds treated with JF27; expression remained at a consistently higher level than in the control plants for 12 h after pathogen infection. The phylogenetic analysis of a partial internal transcribed spacer sequence and the b-tubulin gene identified isolate JF27 as Aspergillus terreus. Taken together, these results suggest that A. terreus JF27 has potential as a growth promoter and could be used to control bacterial speck disease by inducing resistance in tomato plants.

• Molecules and Cells
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• v.45 no.9
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• pp.660-672
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• 2022

The target of rapamycin complex (TORC) plays a key role in plant cell growth and survival by regulating the gene expression and metabolism according to environmental information. TORC activates transcription, mRNA translation, and anabolic processes under favorable conditions, thereby promoting plant growth and development. Tomato fruit ripening is a complex developmental process promoted by ethylene and specific transcription factors. TORC is known to modulate leaf senescence in tomato. In this study, we investigated the function of TORC in tomato fruit ripening using virus-induced gene silencing (VIGS) of the TORC genes, TOR, lethal with SEC13 protein 8 (LST8), and regulatory-associated protein of TOR (RAPTOR). Quantitative reverse transcription-polymerase chain reaction showed that the expression levels of tomato TORC genes were the highest in the orange stage during fruit development in Micro-Tom tomato. VIGS of these TORC genes using stage 2 tomato accelerated fruit ripening with premature orange/red coloring and decreased fruit growth, when control tobacco rattle virus 2 (TRV2)-myc fruits reached the mature green stage. TORC-deficient fruits showed early accumulation of carotenoid lycopene and reduced cellulose deposition in pericarp cell walls. The early ripening fruits had higher levels of transcripts related to fruit ripening transcription factors, ethylene biosynthesis, carotenoid synthesis, and cell wall modification. Finally, the early ripening phenotype in Micro-Tom tomato was reproduced in the commercial cultivar Moneymaker tomato by VIGS of the TORC genes. Collectively, these results demonstrate that TORC plays an important role in tomato fruit ripening by modulating the transcription of various ripening-related genes.

• Reproductive and Developmental Biology
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• v.31 no.4
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• pp.227-233
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• 2007

This study was conducted to examine the mRNA expression of apoptosis-related and imprinted genes and methylation pattern of the differentially methylated region (DMR) of H19 gene in day 35 of SCNT pig fetuses. The day 35 of natural mating (control) or cloned (clone) pig fetuses were recovered from uterus. Endometrium from dam and liver from fetus were obtained, respectively. mRNA expression was evaluated by real-time PCR and methylation pattern was analyzed by bisulfite sequencing method. The Bcl-2 mRNA expression in clone was significantly lower than that of control (p<0.05). The mRNA expression of H19 gene in both endometrium and liver was significantly higher in clone than that of control, respectively (p<0.05). The level of IGF-2 mRNA in liver of clone was significantly lower than that of control (p<0.05), whereas the mRNA expression of IGF2-R gene in liver of clone was significantly higher than that of control (p<0.05). The DMR of H19 was lower methylation pattern in clone than that of control. These results suggest that the aberrant mRNA expression of apoptosis-related and imprinted genes and the lower DMR methylation pattern of imprinted gene may be closely related to the inadequate fetal development of cloned fetus.

• Reproductive and Developmental Biology
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• v.38 no.3
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• pp.99-105
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• 2014

In this study, to further understand the mechanism of animal growth and to develop a miniature transgenic animal model, we constructed and tested tetracycline-inducible RNAi system using shRNA targeting the mRNA of mouse insulin-like growth factor (mIGF-1) or mouse growth hormone receptor (mGHR) gene. Quantitative real-time PCR analysis of mouse liver cell (Hepa1c1c7) cells transfected with these vectors showed 85% or 90% of expression inhibition effect of IGF-1 or GHR, respectively. In ELISA analysis, the protein level of IGF-1 in the cells expressing the shRNA targeting IGF-1 mRNA was reduced to 26% of non-transformed control cells. Unexpectedly, in case of using shRNA targeting GHR, the IGF-1 protein level was decreased to 75% of control cells. Further experiments are needed to explain the lower interference effect of GHR shRNA in IGF-1 protein. Accumulated knowledge of this approach could be applicable to a variety of related biological area including gene function study, gene therapy, development of miniature animals, etc.