• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4281-4287
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• 2014

Background: Methylation of tumor suppressor genes has been investigated in all kinds of cancer. Tumor specific epigenetic alterations can be used as a molecular markers of malignancy, which can lead to better diagnosis, prognosis and therapy. Therefore, the aim of this study was to evaluate the association between gene hypermethylation and expression of fragile histidine triad (FHIT), glutathione S-transferase P1 (GSTP1) and p16 genes and various clinicopathologic characteristics in primary non-small cell lung carcinomas (NSCLC). Materials and Methods: The study included 28 primary non-small cell lung carcinomas, where an additional 28 tissue samples taken from apparently normal safety margin surrounding the tumors served as controls. Methylation-specific polymerase chain reaction (MSP) was performed to analyze the methylation status of FHIT, GSTP1 and p16 while their mRNA expression levels were measured using a real-time PCR assay with SYBR Green I. Results: The methylation frequencies of the genes tested in NSCLC specimens were 53.6% for FHIT, 25% for GSTP1, and 0% for p16, and the risk of FHIT hypermethylation increased among patients with NSCLC by 2.88, while the risk of GSTP1 hypermethylation increased by 2.33. Hypermethylation of FHIT gene showed a highly significant correlation with pathologic stage (p<0.01) and a significant correlation with smoking habit and FHIT mRNA expression level (p<0.05). In contrast, no correlation was observed between the methylation of GSTP1 or p16 and smoking habit or any other parameter investigated (p>0.05). Conclusions: Results of the present study suggest that methylation of FHIT is a useful biomarker of biologically aggressive disease in patients with NSCLC. FHIT methylation may play a role in lung cancer later metastatic stages while GSTP1 methylation may rather play a role in the early pathogenesis.

• 한국응용곤충학회지
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• 제56권1호
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• pp.19-28
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• 2017

폴리드나바이러스(polydnavirus: PDV)는 일부 내부기생봉에 공생하는 이중나선형 DNA 바이러스 분류군이다. Cotesia plutellae bracovirus (CpBV)는 프루텔고치벌(C. plutellae)에 공생하는 일종의 PDV이다. 프루텔고치벌은 어린 배추좀나방(Plutella xylostella) 유충에 기생한다. 기생 초기에 발현하는 CpBV-ELP1 유전자는 혈구세포에 세포독성을 발휘하면서 기주의 세포성 면역을 억제하여 기생에 중요한 역할을 담당하고 있다. 본 연구는 이 유전자를 담배 식물에서 발현하여 해충에 대한 경구독성을 분석하는 데 목적을 두었다. 재조합 CpBV-ELP1 단백질이 배큘로바이러스 발현시스템을 통해 합성되어 세포배양액에 분비되었다. 수거된 세포배양액은 일련의 단백질 분리과정(ammonium sulfate 단백질 분획, size exclusion 크로마토그래피, 이온교환 크로마토그래피)을 통해 CpBV-ELP1 단백질을 분리하는 데 이용되었다. 분리된 rCpBV-ELP1 단백질은 파밤나방(Spodoptera exigua) 혈구에 대한 뚜렷한 세포독성을 보였다. CpBV-ELP1은 파밤나방 5령충에 대해서 혈강 주입하여 살충력을 나타냈고, 엽침지법을 이용하여 경구독성을 갖고 있는 것을 확인하였다. CpBV-ELP1 유전자를 CaMV 35S 유전자 프로모터와 opaline synthase 유전자 전사종결신호를 갖는 pBI121 벡터에 클로닝하여 Agrobacterium tumefaciens LBA4404 세균에 형질전환을 유도하였다. 형질전환된 세균은 담배(Nicotiana tabacum Xanthi)잎에 감염하여 캘러스를 유도하게 하였고 이후 차세대(T1)를 확보하였다. T1 세대 담배는 파밤나방에 대한 해충저항성을 갖고 있음을 확인하였다. 이러한 결과는 CpBV-ELP1 유전자가 형질전환작물을 통해 해충방제에 응용될 수 있다는 것을 제시하고 있다.

• IMMUNE NETWORK
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• 제2권4호
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• pp.242-247
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• 2002

Background: Tumor necrosis factor-alpha (TNF-$\alpha$) is known to play an important role in various conditions such as inflammation, autoimmunity, apoptosis, insulin resistance and sleep induction. Five single nucleotide polymorphisms (SNPs) have been known to affect the transcriptional activities of TNF-$\alpha$: -1,031T/C, -863C/A, -857C/T, -308G/A and -238G/A. Methods: We have investigated 5 SNPs of the promoter region of TNF-$\alpha$ gene, the distribution of 5-locus TNF-$\alpha$ haplotypes, and their haplotypic associations with previously typed HLA-A, -B and -DRB1 loci in 107 healthy unrelated Koreans. TNF-$\alpha$ SNPs were typed using PCR-single-strand conformation polymorphism (SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. Results: The allele frequencies of -1,031C, -863A, -857T, -308A, and-238A, which are known as the high-producer-type, were 19.3%, 15.9%, 14.0%, 5.9%, and 2.9%, respectively. The frequency of -308A allele, known to be associated with autoimmune diseases, was 5.9% in Koreans which was lower than Caucasians (14~17%) and somewhat higher than Japanese (1.7%). Five most common TNF-$\alpha$ haplotypes (-1,031/-863/-857/-308/-238) comprised over 95% of total haplotypes: TCCGG (58.4%), CACGG (14.8%), TCTGG (13.7%), TCCAG (5.3%), and CCCGA (3.1%). Strong positive associations (P<0.001) were observed between TCCGG and B62; between CACGG and B51, $DRB1^*0901$; between TCTGG and B35, B54, B59, $DRB1^*1201$; and between TCCAG and A33, B58, $DRB1^*0301$, $DRB1^*1302$. Five most common extended haplotypes (>3%) comprised around 16% of total haplotypes: A33-B58-TCCAG-$DRB1^*1302$, A24-B52-TCCGG-$DRB1^*1502$, A33-B44-TCCGG-$DRB1^*1302$, A24-B7-TCCGG-$DRB1^*0101$, and A11-B62-TCCGG-$DRB1^*0406$. The distribution of extended HLA and TNF-$\alpha$ haplotypes showed that most of HLA haplotypes were almost exclusively associated with particular TNF-$\alpha$ haplotypes. Conclusion: The results obtained in this study would be useful as basic data for anthropologic studies and disease association studies in Koreans.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.482-493
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• 2005

Biomass is originally photosynthesized from inorgainic compounds such as $CO_2$, minerals, water and solar energy. Recent studies have shown that anaerobic bacteria have the ability to convert recalcitrant biomass such as cellullosic or chitinoic materials to useful compounds. The biomass containing agricultural waste, unutilized wood and other garbage is expected to utilize as feed, food and fuel by microbial degradation and other metabolic functions. In this study we isolated several anaerobic, cellulolytic and chitinolytic bacteria from rumen fluid, compost and soil to study their related enzymes and genes. The anaerobic and cellulolytic bacteria, Clostridium thermocellum, Clostridium stercorarium, and Clostridium josui, were isolated from compost and the chitinolytic Clostridium paraputrificum from beach soil and Ruminococcus albus was isolated from cow rumen. After isolation, novel cellulase and xylanase genes from these anaerobes were cloned and expressed in Escherichia coli. The properties of the cloned enzymes showed that some of them were the components of the enzyme (cellulase) complex, i.e., cellulosome, which is known to form complexes by binding cohesin domains on the cellulase integrating protein (Cip: or core protein) and dockerin domains on the enzymes. Several dockerin and cohesin polypeptides were independently produced by E. coli and their binding properties were specified with BIAcore by measuring surface plasmon resonance. Three pairs of cohesin-dockerin with differing binding specificities were selected. Two of their genes encoding their respective cohesin polypeptides were combined to one gene and expressed in E. coli as a chimeric core protein, on which two dockerin-dehydrogenase chimeras, the dockerin-formaldehyde dehydrogenase and the dockerin-NADH dehydrogenase are planning to bind for catalyzing $CO_2$ reduction to formic acid by feeding NADH. This reaction may represent a novel strategy for the reduction of the green house gases. Enzymes from the anaerobes were also expressed in tobacco and rice plants. The activity of a xylanase from C. stercorarium was detected in leaves, stems, and rice grain under the control of CaMV35S promoter. The digestibility of transgenic rice leaves in goat rumen was slightly accelerated. C. paraputrificum was found to solubilize shrimp shells and chitin to generate hydrogen gas. Hydrogen productivity (1.7 mol $H_2/mol$ glucos) of the organism was improved up to 1.8 times by additional expression of the own hydrogenase gene in C. paraputrficum using a modified vector of Clostridiu, perfringens. The hydrygen producing microflora from soil, garbage and dried pelletted garbage, known as refuse derived fuel(RDF), were also found to be effective in converting biomass waste to hydrogen gas.

• Journal of Plant Biotechnology
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• 제36권1호
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• pp.75-80
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• 2009

산화스트레스에 내성을 지닌 형질전철 고구마 식물체를 개발하기 위해서 산화스트레스에 의해 발현이 강하게 유도되는 SWPA2 프로모터 또는 CaMV 35S 프로모터에 2-Cys peroxiredoxin (Prx) 유전자가 발현되도록 연결한 형질전철 벡터 (pSP-K, pEP-K)를 제작한 후, 각각 Agrobacterium 매개로 형질전환 하였다. 카나마이신 저항성 배발생 캘러스로부터 체세포배발생 과정을 거쳐 100mg/L kanainycin이 포함된 MS 배지에서 소식물체로 발달하였다. Southern 분석으로 외래 유전자가 안정적으로 고구마 게놈 내로 삽입되었음을 확인하였다. 형질전환 고구마 잎 조직을 대상으로 $20{\mu}M$ methyl viologen에 대한 내성 검정을 조사하여 형질전환 고구마 식물체가 비형질전환 식물체 또는 벡터 대조구 식물체 보다 40% 정도 높은 신화스트레스에 대한 내성을 보여주었다. 선발된 형질전환 식물계는 저온, 건조 등의 여러 기지 환경스트레스 내성검정에 이용될 것이며 향후 복합재해 내성 고구마 계통육성에 이용될 수 있을 것으로 기대된다.

• 생명과학회지
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• 제20권9호
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• pp.1314-1323
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• 2010

유전자를 이소성으로 발현하고 억제하는 것은 유전자의 기능 연구에 있어서 매우 유용하다. 본 연구에서는 표적 유전자의 동시 과발현, 조직/발달 단계 특이적 발현 및 스트레스 유도성 발현을 위해 pPZP를 골격으로 다양한 binary 벡터를 제작하고 그 유용성을 검증하였다. 변형된 CaMV 35S 프로모터를 이용하여, 다른 두 개의 유전자를 동시 과발현시키는 binary 벡터를 제작하였고, 이 벡터가 동시에 그리고 같은 장소에서 다른 두 개의 표적 유전자를 과발현 하는데 효과적임을 확인하였다. At2S3, KNAT1 및 LFY 프로모터를 포함하는 조직 또는 발달 단계 특이적 발현 binary 벡터들을 제작하고 분석한 결과, 이 벡터들은 각각 배/유식물 시기, 새싹 끝의 분열조직 및 잎 원기 특이적 발현에 유용하였다. RD29A와 AtNCED3 프로모터를 포함하는 스트레스 유도성 발현 binary 벡터들은 고염, ABA, MV 또는 저온과 같은 비생물성 스트레스에 의한 유전자의 이소성 발현에 유용하였다. 본 연구에서 제작된 binary 벡터들은 표적 유전자의 이소성 발현을 통해 유전자의 생물학적 기능연구, 분자생물학적작용 기작 연구에 유용하게 사용될 것으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4031-4036
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• 2012

Background: The negative signaling provided by interactions of the co-inhibitory molecule, programmed death-1 (PD-1), and its ligands, B7-H1 (PD-L1) and B7-DC (PD-L2), is a critical mechanism contributing to tumor evasion; blockade of this pathway has been proven to enhance cytotoxic activity and mediate antitumor therapy. Here we evaluated the anti-tumor efficacy of AAV-mediated delivery of the extracellular domain of murine PD-1 (sPD-1) to a tumor site. Material and Methods: An rAAV vector was constructed in which the expression of sPD-1, a known negative regulator of TCR signals, is driven by human cytomegalovirus immediate early promoter (CMV-P), using a triple plasmid transfection system. Tumor-bearing mice were then treated with the AAV/sPD1 construct and expression of sPD-1 in tumor tissues was determined by semi quantitative RT-PCR, and tumor weights and cytotoxic activity of splenocytes were measured. Results: Analysis of tumor homogenates revealed sPD-1 mRNA to be significantly overexpressed in rAAV/sPD-1 treated mice as compared with control levels. Its use for local gene therapy at the inoculation site of H22 hepatoma cells could inhibit tumor growth, also enhancing lysis of tumor cells by lymphocytes stimulated specifically with an antigen. In addition, PD-1 was also found expressed on the surfaces of activated CD8+ T cells. Conclusion: This study confirmed that expression of the soluble extracellular domain of PD-1 molecule could reduce tumor microenvironment inhibitory effects on T cells and enhance cytotoxicity. This suggests that it might be a potential target for development of therapies to augment T-cell responses in patients with malignancies.

• Asian-Australasian Journal of Animal Sciences
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• 제29권1호
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• pp.126-133
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• 2016

A gene from Actinomyces sp. Korean native goat (KNG) 40 that encodes an endo-${\beta}$-1,4-glucanase, EG1, was cloned and expressed in Escherichia coli (E. coli) $DH5{\alpha}$. Recombinant plasmid DNA from a positive clone with a 3.2 kb insert hydrolyzing carboxyl methyl-cellulose (CMC) was designated as pDS3. The entire nucleotide sequence was determined, and an open-reading frame (ORF) was deduced. The ORF encodes a polypeptide of 684 amino acids. The recombinant EG1 produced in E. coli $DH5{\alpha}$ harboring pDS3 was purified in one step using affinity chromatography on crystalline cellulose and characterized. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis/zymogram analysis of the purified enzyme revealed two protein bands of 57.1 and 54.1 kDa. The amino terminal sequences of these two bands matched those of the deduced ones, starting from residue 166 and 208, respectively. Putative signal sequences, a Shine.Dalgarno-type ribosomal binding site, and promoter sequences related to the consensus sequences were deduced. EG1 has a typical tripartite structure of cellulase, a catalytic domain, a serine-rich linker region, and a cellulose-binding domain. The optimal temperature for the activity of the purified enzyme was $55^{\circ}C$, but it retained over 90% of maximum activity in a broad temperature range ($40^{\circ}C$ to $60^{\circ}C$). The optimal pH for the enzyme activity was 6.0. Kinetic parameters, $K_m$ and $V_{max}$ of rEG1 were 0.39% CMC and 143 U/mg, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제27권12호
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• pp.1695-1704
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• 2014

Maternal malnutrition during pregnancy may give rise to female offspring with disrupted ovary functions in adult age. Neonatal ovary development predisposes adult ovary function, yet the effect of maternal nutrition on the neonatal ovary has not been described. Therefore, here we show the impact of maternal protein restriction on the expression of folliculogenic and steroidogenic genes, their regulatory microRNAs and promoter DNA methylation in the ovary of neonatal piglets. Sows were fed either standard-protein (SP, 15% crude protein) or low-protein (LP, 7.5% crude protein) diets throughout gestation. Female piglets born to LP sows showed significantly decreased ovary weight relative to body weight (p<0.05) at birth, which was accompanied with an increased serum estradiol level (p<0.05). The LP piglets demonstrated higher ratio of bcl-2 associated X protein/B cell lymphoma/leukemia-2 mRNA (p<0.01), which was associated with up-regulated mRNA expression of bone morphogenic protein 4 (BMP4) (p<0.05) and proliferating cell nuclear antigen (PCNA) (p<0.05). The steroidogenic gene, cytochrome P450 aromatase (CYP19A1) was significantly down-regulated (p<0.05) in LP piglets. The alterations in ovarian gene expression were associated with a significant down-regulation of follicle-stimulating hormone receptor mRNA expression (p<0.05) in LP piglets. Moreover, three microRNAs, including miR-423-5p targeting both CYP19A1 and PCNA, miR-378 targeting CYP19A1 and miR-210 targeting BMP4, were significantly down-regulated (p<0.05) in the ovary of LP piglets. These results suggest that microRNAs are involved in mediating the effect of maternal protein restriction on ovarian function through regulating the expression of folliculogenic and steroidogenic genes in newborn piglets.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2185-2193
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• 2016

Background: The pathogenesis of sporadic colorectal cancer (CRC) is influenced by the patient genetic background and environmental factors. Based on prior understanding, these are classified in two major pathways of genetic instability. Microsatellite instability (MSI) and CPG island methylator phenotype (CIMP) are categorized as features of the hypermethylated prototype, and chromosomal instability (CIN) is known to be indicative of the non-hypermethylated category. Secreted frizzled related protein 2 (SFRP2), APC1A in WNT signaling pathway and the DNA repair gene, O6-methylguanine-DNA methyltransferase (MGMT), are frequently hypermethylated in colorectal cancer. Detection of methylated DNA as a biomarker by easy and inexpensive methods might improve the quality of life of patients with CRC via early detection of cancer or a precancerous condition. Aim: To evaluate the rate of SFRP2 and MGMT hypermethylation in both polyp tissue and serum of patients in south Iran as compared with matched control normal population corresponding samples. Materials and Methods: Methylation-specific PCR was used to detect hypermethylation in DNA extracted from 48 polypoid tissue samples and 25 healthy individuals. Results: Of total polyp samples, 89.5% had at least one promoter gene hypermethylation. The most frequent methylated locus was SFRP2 followed by MGMT-B (81.2 and 66.6 percent respectively). Serologic detection of hypermethylation was 95% sensitive as compared with polyp tissue. No hypermethylation was detected in normal tissue and serum and its detection in patients with polyps, especially of serrated type, was specific. Conclusions: Serologic investigation for detection of MGMT-B, SFRP2 hypermethylation could facilitate prioritization of high risk patients for colonoscopic polyp detection and excision.