• Journal of Microbiology
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• v.35 no.4
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• pp.300-308
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• 1997

The catechol 2,3-dioxygenase (C23O) encoded by the Pseudomonas putida xylE gene was over-produced in Escherichia coli and purified to homogeneity. The activity of the C23O required the reduced form of the Fe(II) ion since the enzyme was highly susceptible to inactivation with hydrogen perocide but reactivated with the addition of ferrous sulfate in conjunction with ascorbic acid. The C23O activity was abolished by treatment with the chemical reagents, diethyl-pyrocarbonate (DEPC), tetranitromethane (TNM), and 1-cyclohexy1-3-(2-morpholinoethyl) car-bodiimidemetho-ρ-toluenesulfontate (CMC), which are modifying reagents of histidine, tyrosine and glutamic acid, respectively. These results suggest that histidine, tyrosine and glutamic acid residues may be good active sites for the enzyme activity. These amino acid residues are conserved residues may be good active sites for the enzyme activity. These amino acid residues are conserved residues among several extradion dioxygenases and have the chemical potential to serveas ligands for Fe(II) coordination. Analysis of random point mutants in the C23O gene derived by PCR technique revealed that the mutated positions of two mutants, T179S and S211R, were located near the conserved His165 amd Hos217 residues, respectively. This finding indicates that these two positions, along with the conserved histidine residues, are specially effective regions for the enzyme function.

• Molecules and Cells
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• v.38 no.6
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• pp.580-586
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• 2015

While increasing evidence indicates the important function of histone methylation during development, how this process influences cardiac development in vertebrates has not been explored. Here, we elucidate the functions of two histone H3 lysine 4 (H3K4) methylation enzymes, SMYD3 and SETD7, during zebrafish heart morphogenesis using gene expression profiling by whole mount in situ hybridization and antisense morpholino oligonucleotide (MO)-based gene knockdown. We find both smyd3 and setd7 are highly expressed within developing zebrafish heart and knock-down of these genes led to severe defects in cardiac morphogenesis without altering the expressions pattern of heart markers, including cmlc2, vmhc, and amhc. Furthermore, double knock-down by coinjection of smyd3 and setd7 MOs caused the synergistic defects in heart development. As similar to knock-down effect, overexpression of these genes also caused the heart morphogenesis defect in zebrafish. These results indicate that histone modifying enzymes, SMYD3 and SETD7, appear to function synergistically during heart development and their proper functioning is essential for normal heart morphogenesis during development.

• Korean Journal of Biological Psychiatry
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• v.15 no.1
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• pp.29-34
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• 2008

Objectives : This study aimed to test potential modifying effects of education on the association between apolipoprotein E ${\varepsilon}4$ (Apo E4) and cognitive decline. Methods : A community cohort(N=683) aged 65 or over completed the Korean version of Mini-Mental State Examination(MMSE-K) at baseline and two years later(1999-2001). Apo E polymorphisms were genotyped, and classified into that with or without Apo E4. Educational levels were categorized into people with or without education. Covariates included demographic(age, gender), life style(smoking, alcohol drinking), clinical (depression, sleep disorder, vascular risk factors) characteristics. Results : The association between Apo E4 and cognitive decline was significant only in the old persons with no education. The interaction term between education and Apo E4 on cognitive decline was significant(p=0.040). Conclusion : Elders with no education might be more vulnerable to the impact of Apo E4 on cognitive decline, which suggests gene-environment interaction.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3507-3511
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• 2014

Background: The prostaglandin-endoperoxide synthase 2 [PTGS2, commonly known as cyclooxygenase-2 (COX-2)] is an enzyme induced by proinflammatory stimuli that is often overexpressed in malignant tissue and involved in the synthesis of prostaglandins and thromboxanes, regulators of processes such as inflammation, cell proliferation, and angiogenesis, all relevant for cancer development. We investigated whether a functional genetic polymorphism, rs5277, in COX-2 may have a risk-modifying effect on sporadic colorectal cancer in an Iranian population. Materials and Methods: We conducted a case-control study on 167 patients with colorectal cancer and 197 cancer-free controls in Taleghani Hospital in Tehran, Iran, between 2007 and 2011. Peripheral blood samples of both groups were processed for DNA extraction and genotyping of the COX-2 gene polymorphism (rs5277) using PCR-RFLP. RFLP results were confirmed by direct sequencing. Logistic regression analysis was performed to calculate the adjusted odds ratio (OR) and 95% confidence interval (95% CI). Results: There was no significant difference in the distribution of COX-2 gene rs5277 polymorphism genotype and the allelic form, among CRC patients compared with the healthy control group (p: 0.867). Conclusions: Our results suggest that rs5277 polymorphism in COX2 could not be a good prognostic indicator for patients with CRC.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.13-16
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• 2000

Microorganisms have been widely employed for the production of useful bioproducts including primary metabolites such as ethanol, succinic acid, acetone and butanol, secondary metabolites represented by antibiotics, proteins, polysaccharides, lipids and many others. Since these products can be obtained in small quantities under natural condition, mutation and selection processes have been employed for the improvement of strains. Recently, metabolic engineering strategies have been employed for more efficient production of these bioproducts. Metabolic engineering can be defined as purposeful modification of cellular metabolic pathways by introducing new pathways, deleting or modifying the existing pathways for the enhanced production of a desired product or modified/new product, degradation of xenobiotics, and utilization of inexpensive raw materials. Metabolic flux analysis and metabolic control analysis along with recombinant DNA techniques are three important components in designing optimized metabolic pathways, This powerful technology is being further improved by the genomics, proteomics, metabolomics and bioinformatics. Complete genome sequences are providing us with the possibility of addressing complex biological questions including metabolic control, regulation and flux. In silico analysis of microbial metabolic pathways is possible from the completed genome sequences. Transcriptome analysis by employing ONA chip allows us to examine the global pattern of gene expression at mRNA level. Two dimensional gel electrophoresis of cellular proteins can be used to examine the global proteome content, which provides us with the information on gene expression at protein level. Bioinformatics can help us to understand the results obtained with these new techniques, and further provides us with a wide range of information contained in the genome sequences. The strategies taken in our lab for the production of pharmaceutical proteins, polyhydroxyalkanoate (a family of completely biodegradable polymer), succinic acid and me chemicals by employing metabolic engineering powered by genomics, proteomics, metabolomics and bioinformatics will be presented.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.359-371
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• 2019

To optimize the expression and secretion of ferritin protein associated with ion storage in the mushroom, Pleurotus eryngii, a recombinant secretion vector, harboring the ferritin gene, was constructed using a pPEVPR1b vector under the control of the CaMV 35S promoter and signal sequence of pathogen related protein (PR1b). The ferritin gene was isolated from the T-Fer vector following digestion with EcoRI and HindIII. The gene was then introduced into the pPEVPR1b secretion vector, and it was then named pPEVPR1b-Fer. The recombinant vector was transferred into P. eryngii via Agrobacterium tumefaciens-mediated transformation. The transformants were selected on MCM medium supplemented with kanamycin and its expression was confirmed by SDS-PAGE and western blotting. Expression of ferritin protein was optimized by modifying the culture conditions such as incubation time and temperature in batch and 20 L airlift type fermenter. The optimal conditions for ferritin production were achieved at 25℃ and after incubating for 8 days on MCM medium. The amount of ferritin protein was 2.4 mg/g mycelia, as measured by a quantitative protein assay. However, the signal sequence of PR1b (32 amino acids) seems to be correctly processed by peptidase and ferritin protein may be targeted in the apoplast region of mycelia, and it might not be secreted in the culture medium. The iron binding activity was confirmed by Perls' staining in a 7.5% non-denaturing gel, indicating that the multimeric ferritin (composed of 24 subunits) was formed in P. eryngii mycelia. Mycelium powder containing ferritin was tested as a feed additive in broilers. The addition of ferritin powder stimulated the growth of young broilers and improved their feed efficiency and production index.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6311-6318
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• 2012

Background: HER2/neu overexpression due to gene amplification is an important factor in breast cancer, modifying the sensitivity to anti-HER2 monoclonal antibody therapy. The clinical significance of HER2 expression in non small cell lung carcinoma (NSCLC) is currently under evaluation. The tumor suppressor gene PTEN negatively regulates the HER2/PI3K/Akt signalling pathway. The purpose of this study was to evaluate the role of simultaneous alteration in HER2 and PTEN protein expression in relation to biological behaviour of NSCLCs. Materials and Methods: Protein expression was determined by immunohistochemistry in sixty-one (n=61) NSCLC cases along with CISH for HER2 gene analysis and detection of chromosome 17 aneuploidy. Patients were followed-up for a period of 34 to 41 months after surgery. Results: HER2 overexpression (2+/3+score) was detected in 17 (27.9%) patients while loss of PTEN expression was observed in 24 (39.3%) cases, low expression in 29 (47.6%) and overexpression in 8 (13.1%). Simultaneous HER2 overexpression and PTEN low/loss of expression were correlated with metastasis (71.4% vs 36.2% p=0.03). Analysis in the subgroup of 22 patients of pTNM stage III with lymph node status N1 or N2 revealed that there was a relationship between the number of positive regional lymph node groups and simultaneous deregulation of the two genes (p=0.04). Multivariate analysis determined that HER2 overexpression was associated with an increasing risk of developing metastases (OR: 4.3; 95%CI: 1.2-15.9; p: 0.03) while PTEN overexpression was associated with lower risk (OR: 0.1; 95%CI: 0.1, 1.0; p: 0.05). Conclusions: Simultaneous HER2/PTEN deregulation is a significant genetic event that leads to a more aggressive phenotype of NSCLC.

• Development and Reproduction
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• v.17 no.1
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• pp.1-8
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• 2013

Osteoprotegerin (OPG) is a secreted glycoprotein that regulates bone resorption by inhibiting differentiation and activation of osteoclast, thereby potentially useful for the treatment of many bone diseases associated with increased bone loss. In this study, we designed a novel cDNA expression cassette by modifying the potent and mammary gland-specific goat ${\beta}$-casein/hGH hybrid gene construct and examined human OPG (hOPG) cDNA expression in transgenic mice. Six transgenic mice all successfully expressed hOPG in their milk at the level of 0.06-2,000 ${\mu}g/ml$. An estimated molecular weight of the milk hOPG was 55 kDa in SDS-PAGE, which is the same as a naturally glycosylated monomer. This hOPG expression was highly specific to the mammary glands of transgenic mice. hOPG mRNA was not detected in any organs analyzed except mammary gland. Functional integrity of milk hOPG was evaluated by TRAP (tartrate-resistant acid phosphatase) activity assay in bone marrow cell cultures. OPG ligand (OPG-L) treatment increased TRAP activity by two fold but it was completely abolished by co-treatment with transgenic milk containing hOPG. Taken together, our novel cDNA expression cassette could direct an efficient expression of biologically active hOPG, a potential candidate pharmaceutical for bone diseases, only in the mammary gland of transgenic mice.

• Clinical and Experimental Pediatrics
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• v.53 no.3
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• pp.273-285
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• 2010

Completion of the human genome project has allowed a deeper understanding of molecular pathophysiology and has provided invaluable genomic information for the diagnosis of genetic disorders. Advent of new technologies has lead to an explosion in genetic testing. However, this overwhelming stream of genetic information often misleads physicians and patients into a misguided faith in the power of genetic testing. Moreover, genetic testing raises a number of ethical, legal, and social issues. Diagnostic genetic tests can be divided into three primary but overlapping categories: cytogenetic studies (including routine karyotyping, high-resolution karyotyping, and fluorescent in situ hybridization studies), biochemical tests, and DNA-based diagnostic tests. DNA-based testing has grown rapidly over the past decade and includes preandpostnatal testing for the diagnosis of genetic diseases, testing for carriers of genetic diseases, genetic testing for susceptibility to common non-genetic diseases, and screening for common genetic diseases in a particular population. Theoretically, once a gene's structure, function, and association with a disease are well established, the clinical application of genetic testing should be feasible. However, for routine applications in a clinical setting, such tests must satisfy a number of criteria. These criteria include an acceptable degree of clinical and analytical validity, support of a quality assurance program, possibility of modifying the course of the diagnosed disease with treatment, inclusion of pre-and postnatal genetic counseling, and determination of whether the proposed test satisfies cost-benefit criteria and should replace or complement traditional tests. In the near future, the application of genetic testing to common diseases is expected to expand and will likely be extended to include individual pharmacogenetic assessments.

• Molecules and Cells
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• v.42 no.1
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• pp.17-27
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• 2019

Ubiquitin-specific protease 44 (USP44) has been implicated in tumor progression and metastasis across various tumors. However, the function of USP44 in prostate cancers and regulatory mechanism of histone-modifying enzymes by USP44 in tumors is not well-understood. Here, we found that enhancer of zeste homolog 2 (EZH2), a histone H3 lysine 27 methyltransferase, is regulated by USP44. We showed that EZH2 is a novel target of USP44 and that the protein stability of EZH2 is upregulated by USP44-mediated deubiquitination. In USP44 knockdown prostate cancer cells, the EZH2 protein level and its gene silencing activity were decreased. Furthermore, USP44 knockdown inhibited the tumorigenic characteristics and cancer stem cell-like behaviors of prostate cancer cells. Inhibition of tumorigenesis caused by USP44 knockdown was recovered by ectopic introduction of EZH2. Additionally, USP44 regulates the protein stability of oncogenic EZH2 mutants. Taken together, our results suggest that USP44 promotes the tumorigenesis of prostate cancer cells partly by stabilizing EZH2 and that USP44 is a viable therapeutic target for treating EZH2-dependent cancers.