• BMB Reports
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• 제49권4호
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• pp.197-198
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• 2016

Although three different research groups have reported successful derivations of human somatic cell nuclear transfer-derived embryonic stem cell (SCNT-ESC) lines using fetal, neonatal and adult fibroblasts, the extremely poor development of cloned embryos has hindered its potential applications in regenerative medicine. Recently, however, our group discovered that the severe methylation of lysine 9 in Histone H3 in a human somatic cell genome was a major SCNT reprogramming barrier, and the overexpression of KDM4A, a H3K9me3 demethylase, significantly improved the blastocyst formation of SCNT embryos. In particular, by applying this new approach, we were able to produce multiple SCNT-ES cell lines using oocytes obtained from donors whose eggs previously failed to develop to the blastocyst stage. Moreover, the success rate was closer to 25%, which is comparable to that of IVF embryos, so that our new human SCNT method seems to be a practical approach to establishing a pluripotent stem cell bank for the general public as well as for individual patients.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.1077-1082
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• 2013

Background: Renal cell carcinoma (RCC) is a malignancy with a poor prognosis. We aimed to explore whether the expression of Long Non-Coding RNA (LncRNA) growth arrest-specific transcript 5 (GAS5) is associated with RCC genesis. Methods: We selected twelve clinical samples diagnosed for renal clear cell carcinoma and found that the LncRNA GAS5 transcript levels were significantly reduced relative to those in adjacent unaffected normal renal tissues. Results: In addition, expression of GAS5 was lower in the RCC cell line A498 than that in normal renal cell line HK-2. Furthermore, using functional expression cloning, we found that overexpression of GAS5 in A498 cells inhibited cell proliferation, induced cell apoptosis and arrested cell cycling. At the same time, the migration and invasion potential of A498 cells were inhibited compared to control groups. Conclusion: Our study provided the first evidence that a decrease in GAS5 expression is associated with RCC genesis and progression and overexpression of GAS5 can act as a tumor suppressor for RCC, providing a potential attractive therapeutic approach for this malignancy.

• KSBB Journal
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• 제20권1호
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• pp.1-11
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• 2005

Recently, there has been extremely active in the research of stem cell biology. Stem cells have excellent potential for being the ultimate source of transplantable cells for many different tissues. Researchers hope to use stem cells to repair or replace diseased or damaged organs, leading to new treatments for human disorders that are currently incurable, including diabetes, spinal cord injury and brain diseases. There are primary sources of stem cells like embryonic stem cells and adult stem cells. Stem cells from embryos were known to give rise to every type of cell. However, embryonic stem cells still have a lot of disadvantages. First, transplanted cells sometimes grow into tumors. Second, the human embryonic stem cells that are available for research would be rejected by a patient's immune system. Tissue-matched transplants could be made by either creating a bank of stem cells from more human embryos, or by cloning a patient's DNA into existing stem cells to customize them. However, this is laborious and ethically contentious. These problems could be overcome by using adult stem cells, taken from a patient, that are treated to remove problems and then put back. Nevertheless, some researchers do not convince that adult stem cells could, like embryonic ones, make every tissue type. Human stem cell research holds enormous potential for contributing to our understanding of fundamental human biology. In this review, we discuss the recent progress in stem cell research and the future therapeutic applications.

• Journal of Microbiology and Biotechnology
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• 제29권6호
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• pp.999-1007
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia in 2012 and related infection cases have been reported in over 20 countries. Roughly 10,000 human cases have so far been reported in total with fatality rates at up to 40%. The majority of cases have occurred in Saudi Arabia with mostly sporadic outbreaks outside the country except for the one in South Korea in 2015. The Korean MERS-CoV strain was isolated from the second Korean patient and its genome was fully sequenced and deposited. To develop virus-specific protective and therapeutic agents against the Korean isolate and to investigate molecular determinants of virus-host interactions, it is of paramount importance to generate its full-length cDNA. Here we report that two full-length cDNAs from a Korean patient-isolated MERS-CoV strain were generated by a combination of conventional cloning techniques and efficient Gibson assembly reactions. The full-length cDNAs were validated by restriction analysis and their sequence was verified by Sanger method. The resulting cDNA was efficiently transcribed in vitro and the T7 promoter-driven expression was robust. The resulting reverse genetic system will add to the published list of MERS-CoV cDNAs and facilitate the development of Korean isolate-specific antiviral measures.

• Biomolecules & Therapeutics
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• 제31권1호
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• pp.48-58
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• 2023

Interferon regulatory factor 3 (IRF3) integrates both immunological and non-immunological inputs to control cell survival and death. Small GTPases are versatile functional switches that lie on the very upstream in signal transduction pathways, of which duration of activation is very transient. The large number of homologous proteins and the requirement for site-directed mutagenesis have hindered attempts to investigate the link between small GTPases and IRF3. Here, we constructed a constitutively active mutant expression library for small GTPase expression using Gibson assembly cloning. Small-scale screening identified multiple GTPases capable of promoting IRF3 phosphorylation. Intriguingly, 27 of 152 GTPases, including ARF1, RHEB, RHEBL1, and RAN, were found to increase IRF3 phosphorylation. Unbiased screening enabled us to investigate the sequence-activity relationship between the GTPases and IRF3. We found that the regulation of IRF3 by small GTPases was dependent on TBK1. Our work reveals the significant contribution of GTPases in IRF3 signaling and the potential role of IRF3 in GTPase function, providing a novel therapeutic approach against diseases with GTPase overexpression or active mutations, such as cancer.

• 생명과학회지
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• 제27권6호
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• pp.617-622
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• 2017

본 연구에서는 zebrafish에 사람의 cyt $b_5$ 유전자를 microinjection하여 발현시키고, 그 결과를 형광으로 확인하였다. HeLa cell에서 RT-PCR을 진행한 결과 414 bp의 cyt $b_5$ band가 증폭되었다. 염기서열 분석으로 재확인된 cyt $b_5$ insert를 pEGFP-N3의 형광 vector에 클로닝하였고, 이렇게 준비된 pEGFP-N3-cyt $b_5$ plasmid DNA를 1세 포기의 수정란에 microinjection하였다. cyt $b_5$를 microinjection한 치어를 형광현미경으로 관찰한 결과 대조군 치어보다 훨씬 선명한 형광을 띠는 것이 확인되었다. 최종적으로 치어에서 RNA를 분리하여 RT-PCR하였고 전기영동과 DNA sequencing으로 fusion 단백질의 발현을 재확인하였다. Cyt $b_5$의 발현으로 인해 zebrafish의 생존율이 다소 떨어지는 것으로 확인되었기에 독성 문제를 해결하기 위한 연구가 계속 필요할 것으로 사료된다. 이 연구는 향후 cyt $b_5$가 결핍되었을 경우 발생할 수 있는 여러 질병들을 유전자 차원에서 치료하고, 유용 유전자 클로닝을 위한 기술 개발에 발판이 될 수 있을 것으로 기대된다.

• KSBB Journal
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• 제19권5호
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• pp.341-347
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• 2004

Several gene delivery therapies are being developed for treatment of serum protein deficiency. EPO is one of the most promising therapeutic agent for this treatment which is currently being investigated in depth. This study has the ultimate purpose of improving the gene delivery system for an increase of red blood cell production. A plasmid DNA was constructed smaller than other plasmids for an increase in penetration into animal cells, and two genes were cloned into each vector as a co-delivery system to express erythropoietin, and interluekin-3 or thrombopoietin, which can act on erythroid cell, thus activating hematopoiesis synergically. This co-delivery system has an advantage of decreasing the labour required for industrial production of DNA vaccine. A new plasmid vector, pVAC, in size 2.9 kb, was constructed with the essential parts from PUC 19 and pSectagB, which is much smaller than other plasmid vector and is the size of 2.9 kb. Co-delivery system was constituted by cloning human erythropoietin with each of human interluekin-3 gene or human thrombopoietin gene into both pVAC and pSectagB. As a result, the transfection efficiency of pVAC was higer than that of pSectagB in vitro, and hematocrit level of the mice injected with pVAC is higher than that of other mice. And co-delivery system, made of several plasmid DNAs, was expressed in vitro.

• Molecules and Cells
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• 제39권3호
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• pp.242-249
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• 2016

A balance between production and degradation of reactive oxygen species (ROS) is critical for maintaining cellular homeostasis. Increased levels of ROS during oxidative stress are associated with disease conditions. Antioxidant enzymes, such as extracellular superoxide dismutase (EC-SOD), in the extracellular matrix (ECM) neutralize the toxicity of superoxide. Recent studies have emphasized the importance of EC-SOD in protecting the brain, lungs, and other tissues from oxidative stress. Therefore, EC-SOD would be an excellent therapeutic drug for treatment of diseases caused by oxidative stress. We cloned both the full length (residues 1-240) and truncated (residues 19-240) forms of human EC-SOD (hEC-SOD) into the donor plasmid pFastBacHTb. After transposition, the bacmid was transfected into the Sf9-baculovirus expression system and the expressed hEC-SOD purified using FLAG-tag. Western blot analysis revealed that hEC-SOD is present both as a monomer (33 kDa) and a dimer (66 kDa), as detected by the FLAG antibody. A water-soluble tetrazolium (WST-1) assay showed that both full length and truncated hEC-SOD proteins were enzymatically active. We showed that a potent superoxide dismutase inhibitor, diethyldithiocarbamate (DDC), inhibits hEC-SOD activity.

• 한국축산식품학회지
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• 제39권4호
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• pp.601-609
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• 2019

Bifidobacterium longum KACC 91563 secretes family 5 extracellular solute-binding protein via extracellular vesicle. In our previous work, it was demonstrated that the protein effectively alleviated food allergy symptoms via mast cell specific apoptosis, and it has revealed a therapeutic potential of this protein in allergy treatment. In the present study, we cloned the gene encoding extracellular solute-binding protein of the strain into the histidine-tagged pET-28a(+) vector and transformed the resulting plasmid into the Escherichia coli strain BL21 (DE3). The histidine-tagged extracellular solute-binding protein expressed in the transformed cells was purified using Ni-NTA affinity column. To enhance the efficiency of the protein purification, three parameters were optimized; the host bacterial strain, the culturing and induction temperature, and the purification protocol. After the process, two liters of transformed culture produced 7.15 mg of the recombinant proteins. This is the first study describing the production of extracellular solute-binding protein of probiotic bacteria. Establishment of large-scale production strategy for the protein will further contribute to the development of functional foods and potential alternative treatments for allergies.

• 생명과학회지
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• 제28권3호
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• pp.275-283
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• 2018

인간 섬유아세포 성장인자는 조직 생성 및 상처 치료 효과로 인해 상업적으로 중요한 치료제 또는 화장품소재로서 가능성이 높다. 피부 조직에 침투성을 부여하여 치료효과를 높이기 위해서 단백질 전달 도메인인 PTD를 FGF에 융합을 시도하고 있으며 피부로의 투과능력과 그로인한 치료 효과에 대한 연구도 진행되고 있다. 그러나, PTD가 FGF 단백질의 N- 또는 C-말단에 결합 되었을 때 PTD의 위치가 대장균 발현시스템에서 재조합단백질 접힘 및 안정성, 그리고 결국 피부로의 도입능력에 상당한 영향을 미치는지에 대해서는 알려져 있지 않다. 여기에서 우리는 대조군으로 PTD가 융합되지 않은 인간 염기성 섬유아세포 성장인자(FGF2)와 PTD가 FGF2의 N-말단 또는 C-말단에 융합된 FGF2 복합체를 중합효소연쇄반응(OE-PCR)을 통해 클로닝 하였다. 그 다음 이들 재조합 FGF2의 단백질 발현 및 특성을 확인하고 마우스 등 피부를 이용하여 조직 내로의 도입 능력을 조사 하였다. 결과적으로, 불용성 PTD-FGF2 (N 말단 융합)와는 달리 대조군 FGF2와 FGF2-PTD 융합 단백질(C- 말단 융합)은 가용성 형태로 발현되어 재조합단백질 획득이 용이하였고, 마우스 피부 도입능력은 FGF2-PTD 융합단백질에서만 나타내 보였다. 우리의 결과는 C-말단에 융합된 FGF2-PTD 융합단백질이 발현, 정제, 피부 투과능력의 측면에서 다른 두 옵션들보다 노동, 비용, 시간면에서 보다 더 효율적일 수 있음을 시사한다.