• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.55-55
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• 2003

The random insertion of useful gene in genome has been a common method to produce transgenic animals. This method is inefficient for induction of high levels gene expression in transgenic animals. To improve this limit, we tried to develop the system which target the gene at the specific genomic region. Thus, in our experiment, the vector system to target the human thrombopoietin (TPO) gene was developed. Targeting vector including TPO, neo and DT genes was transfrcted into bovine embryonic fibroblasts (bEF) or bovine ear skin fibroblasts (bESF). First of all, we determined concentration of the geneticin (G418) for selection of transfected cell lines. Our results showed that 1200 and 900 $\mu\textrm{g}$/ml of G418 were the most proper for selection of transfscted bEF and bESF cells. In this study, lipofectamine was used as a transfection reagent. Thus, the proper ratio of DNA:lipofectamine for transfection was also required to elevate targeting efficiency in primary mammalian cells. Our result indicates that the most proper ratios of DNA:lipofectamine were 4:2 and 1:2 in bEF and bESF cells. According to the optimized these conditions, single colonies were picked following transfection and were analyzed by PCR. More than 90% of the single colonies have TPO gene. However, there were no colonies with targeted TPO at the specific genomic region. Therefore, further experiments to select the specifically targeted colonies and to find more efficient methods such as reducing selection time and shortening a size of TPO gene are required.

• Reproductive and Developmental Biology
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• 제33권2호
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• pp.93-98
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• 2009

In this study, bovine Dnmt1 cDNA was sequenced and detected Dnmt1 mRNA level in bovine tissues by northern blot, methylation pattern of genome by southern blot, specific localization of Dnmt1 in mouse and bovine preimplantation embryos by immunocytostaining and Dnmt1 protein level in ovary and testis by western blot. Bovine Dnmt1 cDNA sequence showed more homology with that of human than mouse and rat. The RNA level of Dnmt1 was 10 times higher expression in placenta than other tissues. This indicates that placenta was hypermethylated compared to others organs. The genomic DNA could not be cut by a specific restriction enzyme (HpaII) in placenta, lung and liver of bovine. It suggests that Dnmt1 in some somatic cells was already methylated. Dnmt1, which has the antibody epitope 1316~1616, was distributed in nucleus and cytoplasm including the stage of pronuclear stage and maturation of oocyte and gradually weaken to blastocyst stage compare to negative. In addition, Dnmt1 was strongly expressed in tetraploid embryo and cloned 8-cell than IVF 8-cell. An aberrant pattern of DNA methylation in cloned embryo may be abnormal development of fetus, embryonic lethality and placenta dysfunction. The somatic specific band (190kDa) was appeared in ovary and testis, but oocyte specific band (175kDa) was not. Further investigations are necessary to understand the complex links between the methyltransferases and the transcriptional activity of genes in the cloned bovine tissues.

• The Korean Journal of Physiology and Pharmacology
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• 제21권3호
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• pp.353-360
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• 2017

Several human diseases have been associated with mitochondrial voltage-dependent anion channel-1 (VDAC1) due to its role in calcium ion transportation and apoptosis. Recent studies suggest that VDAC1 may interact with endothelium-dependent nitric oxide synthase (eNOS). Decreased VDAC1 expression may limit the physical interaction between VDAC1 and eNOS and thus impair nitric oxide production, leading to cardiovascular diseases, including pulmonary arterial hypertension (PAH). In this report, we conducted meta-analysis of genome-wide expression data to identify VDAC1 influenced genes implicated in PAH pathobiology. First, we identified the genes differentially expressed between wild-type and Vdac1 knockout mouse embryonic fibroblasts in hypoxic conditions. These genes were deemed to be influenced by VDAC1 deficiency. Gene ontology analysis indicates that the VDAC1 influenced genes are significantly associated with PAH pathobiology. Second, a molecular signature derived from the VDAC1 influenced genes was developed. We suggest that, VDAC1 has a protective role in PAH and the gene expression signature of VDAC1 influenced genes can be used to i) predict severity of pulmonary hypertension secondary to pulmonary diseases, ii) differentiate idiopathic pulmonary artery hypertension (IPAH) patients from controls, and iii) differentiate IPAH from connective tissue disease associated PAH.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9797-9800
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• 2014

Background: Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. Alu elements are among the most prevalent repetitive sequences and constitute 11% of the human genome. Although Alu methylation has been evaluated in many types of cancer, few studies have examined the levels of this modification in serum from NPC patients. Objective: To compare the Alu methylation levels and patterns between serum from NPC patients and normal controls. Materials and Methods: Sera from 50 NPC patients and 140 controls were examined. Quantitative combined bisulfite restriction analysis-Alu (qCOBRA-Alu) was applied to measure Alu methylation levels and characterize Alu methylation patterns. Amplified products were classified into four patterns according to the methylation status of 2 CpG sites: hypermethylated (methylation at both loci), partially methylated (methylation of either of the two loci), and hypomethylated (unmethylated at both loci). Results: A comparison of normal control sera with NPC sera revealed that the latter presented a significantly lower methylation level (p=0.0002) and a significantly higher percentage of hypomethylated loci (p=0.0002). The sensitivity of the higher percentage of Alu hypomethyted loci for distinguishing NPC patients from normal controls was 96%. Conclusions: Alu elements in the circulating DNA of NPC patients are hypomethylated. Moreover, Alu hypomethylated loci may represent a potential biomarker for NPC screening.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.651-660
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• 2006

Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.

• 지능정보연구
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• 제9권2호
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• pp.101-119
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• 2003

Achieving the beneficiary goal of recent discovery in human genome project still needs a way to retrieve and analyze the exponentially expanding bio-related information. Research on bio-related fields naturally applies knowledge discovered to the current problem and make inferences to extract new information where shared concepts and data containing information need to be defined and used in a coherent way. In such a professional domain, while the need to help users reduce their work and to improve search results has been emerged, methods for systematic retrieval and adequate exchange of relevant information are still in their infancy. The design of our system aims at improving the quality of information retrieval in a professional domain by utilizing both corpus-based and concept-based ontology. Meta-rules of helping users to make an adequate query are formed into an ontology in the domain. The integration of those knowledge permits the system to retrieve relevant information in a more semantic and systematic fashion. This work mainly describes the query models with details of GUI and a secondary query generation of the system.

• Animal cells and systems
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• 제9권2호
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• pp.87-94
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• 2005

Spindle position checkpoint monitors the orientation of mitotic spindle for proper segregation of replicated chromosomes into mother cell and the daughter, and prohibits mitotic exit when mitotic spindle is misaligned. BUB2 forms one of the key upstream element of spindle position checkpoint in budding yeast, but its functional homologues have not been identified in higher eukaryotes. Here, we analyzed the functions of two putative BUB2 homologues of C. elegans in the spindle orientation checkpoint. From the C. elegans genome database, we found that two open reading frames (ORFs), F35H12_2 and C33F10_2, showed high sequence homology with BUB2. We obtained the expressed sequence tag (EST) clones for F35H12_2 (yk221d4) and C33F10_2 (yk14e10) and verified the full cDNA for each ORF by sequencing and 5' RACE with SL1 primer. The functional complementation assays of yk221d4 and yk14e10 in ${\Delta}bub2$ of S. cerevisiae revealed that these putative BUB2 homologues of C. elegans could not replace the function of BUB2 in spindle position checkpoint and mitotic exit. Our attempt to document the component of spindle position checkpoint in metazoans using sequence homology was not successful. This suggests that structural information about its components might be required to identify functional homologues of the spindle position checkpoint in higher eukaryotes.

• 한국약용작물학회지
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• 제12권5호
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• pp.406-414
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• 2004

Resveratrol, which is both a phytoalexin with antifungal activity and a phytochemical associated with reduced cancer risk and reduced cardiovascular disease, is synthesized in a limited number of plant species including peanut. Resveratrol synthesis is catalyzed by the enzyme stilbene synthase including resveratrol synthase (RS). Resveratrol synthase gene (RS3) obtained from peanut, Arachis hypogaea, Fabaceae has been transferred into chinese foxglove, Rehmannia glutinosa by using Agrobacterium mediated transformation. RS t-DNA introduced to chinese foxglove (R. glutinosa L) by transformation and its reaction product, $resveratrol-3-O-{\beta}-D-glucoside$ was isolated and characterized using HPLC. Also its biological effects was tested in inhibition of the lipid peroxidation of mouse LDL by glycosylated stilbenes derivatives obtained from transgenic plants. $Resveratrol-3-O-{\beta}-D-glucoside$ isolated from transgenic R. glutinosa L. showed antimicrobial activity of the growth inhibition zone against Escherichia coli and Salmonella typhimurium. Therefore, this compound can be contributed to be useful as a phytoalexin for plant health as well as a phytochemical for human health.

• 한국컴퓨터정보학회논문지
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• 제17권11호
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• pp.141-148
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• 2012

인간 유전체 정보와 관련된 기술이 발전함으로 인하여 이를 이용한 질환 또는 질병에 대한 연관성을 분석하여 그 위험도나 치료 예후 등에 대한 예측하기 위한 연구가 활발히 진행되고 있다. 이러한 연구의 대부분은 대표적인 질적 표현형을 대상으로 하는 환자-대조군 연구(case-control study) 방법을 이용하고 있으며 양적 표현형에 대해서는 개별 단일 염기 변이의 연관성을 회기 분석 방법을 이용하여 규명하는 연구가 주로 수행되고 있다. 특히 복합 질병(complex disease)에 대한 위험도를 예측하기 위한 연구의 경우 흔한 변이 흔한 질환(common variants common disease)의 가정아래 주로 각각의 단일 염기 변이가 보이는 연관성 정보를 기반으로 진행되고 있으며 여러 변이의 상호 작용에 의한 영향을 분석한 결과는 상대적으로 미비하다. 이 논문에서는 양적 표현형에 대한 SNP의 연관성을 분석하고 그 결과로 발견된 SNP을 이용하여 대상 표현형의 값을 예측하기 위한 분류기를 구성하고 그 성능을 평가하였으며 분류기의 단일 염기 변이의 선택에 있어서 각각의 단일 염기 변이의 연관성을 고려할 때와 단일 염기 변이의 쌍이 보이는 연관성을 고려할 때의 분류 성능을 비교하였다.

• Journal of Chest Surgery
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• 제33권1호
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• pp.60-67
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• 2000

Background: Microsatellites are short-tandem repeated uncleotide sequences present throughout the human genome. Alterations of microsatellites have been termed microsatellite instability(MI). It has been generally known that microsatellite instability detected in hereditary non-polyposis colorectal cancer (HNPCC) reflects genetic instability that is caused by impairments of DNA mismatch repair system regarding as a novel tumorigenic mechanism. A number of studies reported that MI occurred at varying frequencies in non-small cell lung carcinoma (NSCLC). However It has been unproven whether MI could be a useful market of genetic instability and have a clinical significance in NSCLC. Material and Method : We have examined whether MI can be observed in thirty NCSLC using polymerase chain reaction whether such alterations are associated with other molecular changes such as p53, K-ras and c-myc oncoproteins expression detected by immunohistochemical stain,. Result: MI(+) was observed in 16.6%(5/30) and MI(-) was 83.3% (25/30) Average age was 50$\pm$7.5 year-old in MI(+) group and 57$\pm$6.6 year-old in MI(-) group. Two year survival rate in MI(=) group (20% 1/5) was worse than MI(-) group (64% 16/25) with a statistic difference. (P=0.04) The positive rate of K-ras oncoprotein expression and simultaneous expression of 2 or 3 oncoproteins expression were higher in MI(+) group than MI(-) group with a statistic difference(P=0.05, P=0.01) Conclusion: From, these results the authors can conclude that MI is found in some NSCLC and it may be a novel tumorigenic mechanism in some NSCLC. We also conclude that MI could be used as another poor prognostic factor in NSCLS.