• Journal of Industrial Technology
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• v.31 no.A
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• pp.71-78
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• 2011

As the need for predicting the flood stage of river from torrential downpouring caused by climate change is increasingly emphasized, the study, centered on the area of Gangwon-do Inje-gun and Jeongseon-gun of local river, is to develop peak water level regression equation by rainfall. Through the correlation between rainfall and peak water level, it is confirmed that rainfall according to duration and peak water level have a high correlation coefficient. Based on this, a relational expression of rainfall and peak water level is verified and then the adequacy of the calculated expression is analyzed and the result shows that a very accurate prediction is not easy to achieve but a rough prediction of the change of water level at each point is possible.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.576-583
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• 2009

G protein-coupled receptor 43 (GPR43) is a newly-discovered short-chain free fatty acid receptor and its functions remain to be defined. The objective of this study was to investigate the function of GPR43 on lipolysis. We successfully cloned the GPR43 gene from the pig (EU122439), and measured the level of GPR43 mRNA in different tissues and primary pig adipocytes. The expression level of GPR43 mRNA was higher in adipose tissue and increased gradually with adipocyte differentiation. Then we examined GPR43 mRNA level in different types, growth-stages and various regions of adipose tissue of pigs. The results showed that the expression level of GPR43 mRNA was significantly higher in adipose tissue of obese pigs than in lean pigs, and the expression level also gradually increased as age increased. We further found that the abundance of GPR43 mRNA level increased more in subcutaneous fat than visceral fat. Thereafter, we studied the correlation between GPR43 and lipid metabolism-related genes in adipose tissue and primary pig adipocytes. GPR43 gene had significant negative correlation with hormone-sensitive lipase gene (HSL, r = -0.881, p<0.01) and triacylglycerol hydrolase gene (TGH, r = -0.848, p<0.01) in adipose tissue, and had positive correlation with peroxisome proliferator-activated receptor $\gamma$ gene ($PPAR_{\gamma}$, r = 0.809, p<0.01) and lipoprotein lipase gene (LPL, r = 0.847, p<0.01) in adipocytes. In addition, we fed different concentrations of docosahexaenoic acid (DHA) to mice, and analyzed expression level changes of GPR43, HSL and TGH in adipose. The results showed that DHA down-regulated GPR43 and up-regulated HSL and TGH mRNA levels; GPR43 also had significant negative correlation with HSL (low: r = -0.762, p<0.01; high: r = -0.838, p<0.01) and TGH (low: r = -0.736, p<0.01; high: r = -0.586, p<0.01). Our results suggested that GPR43 is a potential factor which regulates lipolysis in adipose tissue, and DHA as a receptor of GPR43 might promote lipolysis through down-regulating the expression of GPR43 mRNA.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.128-137
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• 2023

Transcriptome analysis revealed that the sinR gene encoding a transition-state regulator of Bacillus pumilus, genetically close to B. subtilis, was expressed at high levels during growth. The sinR gene is the second gene of the sinIR operon consisting of three promoters and two structural genes in B. subtilis. This study used the sinIR promoter of B. subtilis DB104 to construct a recombinant protein expression system. First, the expression ability depending on the number of sinIR promoter was investigated using enhanced green fluorescent protein (eGFP). The expression level of eGFP was slightly higher when using two promoters (Psin2) than using original promoters. The Psin2 promoter was further engineered by modifying the repressor binding site and -35 and -10 regions. Shine-Dalgarno (SD) sequence of the sinI gene was modified to the consensus sequence. Finally, combining the engineered Psin2 promoter with the modified SD sequence increased the expression level of eGFP by about 13.4-fold over the original promoter. Our results suggest that the optimized sinIR promoter could be used as a novel tool for recombinant protein expression in B. subtilis.

• Biomedical Science Letters
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• v.8 no.3
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• pp.127-135
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• 2002

Anterior subcapsular cataract was developed by opacification with transdifferentiation and abnormal proliferation of lens epithelial cells (LECs) and pathological accumulation of extracellular matrix (ECM). After-cataract also be caused by a similar transdifferentiation of LECs remaining after surgery and the accompanying increase of ECM deposits. It is blown that prostaglandin E2 and cytokine, such as TGF-$\beta$, bFGF, and IL-1, were associated with abnormal proliferation and transdifferentiation of LECs. The aim of this study was to detect the expression of transforming growth factor-$\alpha$ (TGF-$\alpha$), transforming growth factor-$\beta_1$(TGF-$\beta_1$) and basic fibroblast growth factor (bFGF) in LECs of senile and diabetic cataract. The expressions of these growth factors in lens epithelial cells were determined. The sample for growth factor determination were collected in senile cataract patients without metabolic disorder, especially diabetes mellitus and diabetic cataract patients. The mRNA expression of growth factors was detected by semi-quantitative reverse transcription - polymerase chain reaction (RT-PCR) followed by Southern blot analysis. Statistics were analysed using Wilcoxon rank sum test. Semi-quantitative RT-PCR/southern analysis of RNA obtained from thirty surgical specimens demonstrated that the level of mRNA expression of TGF-$\alpha$, -$\beta_1$ and bFGF was increased in diabetic cataract lens tissues compared with senile cataract specimens but non-significant, bFGF and TGF-$\beta_1$ mRNA expression were detected in most patients, expression level of TGF-$\beta_1$ was most high on the basis of normal ocular concentration. Detection rate of TGF-$\alpha$ in diabetic cataract was 1.5 fold higher than in senile cataract (P=0.098). TGF-$\alpha$, TGF-$\beta_1$, and bFGF mRNA expression of LECs were detected in senile and diabetic cataract. In both patient groups, expression level of TGF-$\beta_1$, mRNA was high, so We suggest TGF-$\beta_1$ strong influence in development of senile cataract and of diabetic cataract also. TGF-$\alpha$ expression level was similar but more frequently detected in diabetic cataract than in senile cataract. In conclusion, TGF-$\alpha$ may be associated with early development of diabetic cataract.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.321-326
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• 2000

To examine the feasibility of the long-term production of the human granulocyte colony stimulating factor (hG-CSF) using the $_{L}-arabinose$ promoter system of Escherichia coli, flask relay culture and cyclic fed-batch culture were performed. In the flask relay culture, it was found that the pismid was maintained stably up to about 170 generations in an uninduced condition, whereby the cells could also maintain the capability of expressing hG-CSF expression were maintained stably up to at least 100 generations. In contrast, in the cyclid fed-batch culture, segregational plasmid instability was observed within about 4 generations after induction, even though the cell growth and hG-CSF production reached their maximum balues, 78.0 g/l of dry cell weight and 7.0 g/l of hG-CSF, respectively. It would appear that, when compared to the flask relay culture, the high-cell density and high-level expression of hG-CSF in the cyclic fed-batch cultrure led to the segregational plasmid instability; in other words, a severe metabolic burden existe on the cells due to the high-level expression of hG-CSF. Accordingly, based on these long-term cultures, the segregational and structural plasmid instability was observed and a strategy to overcome such problems could be designed.

• KSBB Journal
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• v.8 no.2
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• pp.133-142
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• 1993

The effects of genetic and environmental factors on productivity of a cloned protein were studied in recombinant Saccharomyces cerevisiae. Plasmid stability and copy level were very high for a $REP^+$ system(at ca. 10 generations, stability: 65-90%, plasmid copy number per cell: 40-200), whereas these were very low for a yep- system(at ca. 10 generations, stability: 30%, plasmid copy number per cell 20). In plasmids containing the $2{\mu}m$ circle genome, a $[cir^o]$ strain was a preferred host cell since the plasmid stability and the copy number in a $[cir^o]$ strain were higher than in a $[cir^+]$strain. Cloned gene expression was dependent on plasmid copy number and stability. The inducer (galactose) level played a very important role in cloned lacZ gene expression, showing that a galactose concentration of 0.8% was sufficient for induction of gene expression. Induction rate was very fast in the case of plasmids exhibiting high stability and copy number by a factor of 4 to 25. The time to reach the peak value of gene expression was longer when galactose was added at the start of fermentation (ca. 26 hours) than at the mid-exponential phase (ca. 6 hours). Glucose repression was reduced by a factor of 2 to 5 as the relative inducer level increased.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.169-175
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• 2016

Here, we investigated whether hyperglycemia and/or free fatty acids (palmitate, PAL) affect the expression level of bone morphogenic protein 4 (BMP4), a proatherogenic marker, in endothelial cells and the potential role of BMP4 in diabetic vascular complications. To measure BMP4 expression, human umbilical vein endothelial cells (HUVECs) were exposed to high glucose concentrations and/or PAL for 24 or 72 h, and the effects of these treatments on the expression levels of adhesion molecules and reactive oxygen species (ROS) were examined. BMP4 loss-of-function status was achieved via transfection of a BMP4-specific siRNA. High glucose levels increased BMP4 expression in HUVECs in a dose-dependent manner. PAL potentiated such expression. The levels of adhesion molecules and ROS production increased upon treatment with high glucose and/or PAL, but this eff ect was negated when BMP4 was knocked down via siRNA. Signaling of BMP4, a pro-inflammatory and pro-atherogenic cytokine marker, was increased by hyperglycemia and PAL. BMP4 induced the expression of inflammatory adhesion molecules and ROS production. Our work suggests that BMP4 plays a role in atherogenesis induced by high glucose levels and/or PAL.

• Animal cells and systems
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• v.2 no.3
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• pp.403-410
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• 1998

The Tcf-1 (T cell specific factor-1) is a transcription factor uniquely expressed in T-lineage cells. Its expression is developmentally regulated, which is high in the specific stage of immature thymocytes, but is much lower in mature T cells. We cloned the Tcf-1 gene by subtractive hybridization and found it to be highly expressed in the thymus compared to the mRNA level in the spleen as expected. Since apoptosis occurs enormously in the thymus, we were interested in whether Tcf-1 gene expression could be regulated by such a high level of apoptotic assault. By using T cell hybridoma 70.7 cells, we induced apoptosis by incubating cells with anti-CD3 antibody in vitro. After apoptosis induction, Tcf-1 mRNA level was found to be significantly reduced compared to normal cells. Since Tcf-1 is a transcription factor for the CD3-e gene, we tested how CD3-e expression is regulated in apoptotic cells. The surface level of CD3-e protein is also down-regulated after apoptosis induction. Such a down-modulation of CD3-e protein would reduce the TCR/CD3 complex on the cell surface, which would be an important regulator for T cell apoptosis.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.451-458
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• 2013

The human gastric pathogen Helicobacter pylori (Hp) has been considered a microaerophile. However, we recently reported that, when supplied with 10% $CO_2$, Hp growth is stimulated by an atmospheric level of $O_2$, suggesting that Hp is a capnophilic aerobe. In this study, we investigated the effects of aerobic $O_2$ tension on Hp cells by comparing gene expression profiles of cultures grown under microaerobic and aerobic conditions in the presence of 10% $CO_2$. The results showed that overall differences in gene expression in Hp cells grown under the two $O_2$ conditions were predominantly growth-phase-dependent. At 6 h, numerous genes were down-regulated under the aerobic condition, accounting for our previous observation that Hp growth was retarded under this condition. At 36 h, however, diverse groups of genes involved in energy metabolism, cellular processes, transport, and cell envelope synthesis were highly up- or down-regulated under the aerobic condition, indicating a progression of the cultures from the log phase to the stationary phase. The expression of several oxidative stress-associated genes including tagD, katA, and rocF was induced in response to aerobic $O_2$ level, whereas trxA, trxB, and ahpC remained unchanged. Altogether, these data demonstrate that aerobic $O_2$ tension is not detrimental to Hp cells but stimulates Hp growth, supporting our previous finding that Hp may be an aerobic bacterium that requires a high $CO_2$ level for its growth.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.1003-1010
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• 2008

The objective of the present study was to identify differences in the expression levels of liver proteins between healthy and ketotic cows, establish a liver metabolic interrelationship of ketosis and elucidate the metabolic characteristics of the liver during ketosis. Liver samples from 8 healthy multiparous Hostein cows and 8 ketotic cows were pooled by health status and the proteins were separated by two-dimensional-electrophoresis (2D-E). Statistical analysis of gels was performed using PDQuest software 8.0. The differences in the expression levels of liver proteins (p<0.05) between ketotic and healthy cows were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF-TOF) tandem mass spectrometry. Five enzymes/proteins were identified as being differentially expressed in the livers of ketotic cows: expression of 3-hydroxyacyl-CoA dehydrogenase type-2 (HCDH), acetyl-coenzyme A acetyltransferase 2 (ACAT) and elongation factor Tu (EF-Tu) were down-regulated, whereas that of alpha-enolase and creatine kinase were up-regulated. On the basis of this evidence, it could be presumed that the decreased expression of HCDH, which is caused by high concentrations of acetyl-CoA in hepatic cells, in the livers of ketotic cows, implies reduced fatty acid ??oxidation. The resultant high concentrations of acetyl-CoA and acetoacetyl CoA would depress the level of ACAT and generate more ??hydroxybutyric acid; high concentrations of acetyl-CoA would also accelerate the Krebs Cycle and produce more ATP, which is stored as phosphocreatine, as a consequence of increased expression of creatine kinase. The low expression level of elongation factor Tu in the livers of ketotic cows indicates decreased levels of protein synthesis due to the limited availability of amino acids, because the most glucogenic amino acids sustain the glyconeogenesis pathway; thus increasing the level of alpha-enolase. Decreased protein synthesis also promotes the conversion of amino acids to oxaloacetate, which drives the Krebs Cycle under conditions of high levels of acetyl-CoA. It is concluded that the livers of ketotic cows possess high concentrations of acetyl-CoA, which through negative feedback inhibited fatty acid oxidation; show decreased fatty acid oxidation, ketogenesis and protein synthesis; and increased gluconeogenesis and energy production.