• BMB Reports
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• v.43 no.4
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• pp.250-256
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• 2010

Natural phosphodiester bond CpG-DNA that contains immunomodulatory CpG motifs (PO-DNA) upregulates the expression of proinflammatory cytokines and induces an Ag-driven Th1 response in a CG sequence-dependent manner in mice. In humans, only phosphorothioate backbone-modified CpG-DNA (PS-DNA) and not PO-DNA has immunomodulatory activity. In this study, we found that liposome-encapsulated PO-DNA upregulated the expression of human $\beta$-defensin-2 (hBD-2) and major histocompatibility class II molecules (HLA-DRA) in a CG sequence-dependent and liposome- dependent manner in human B cells. Of the three different liposomes, DOTAP has the unique ability to enhance the immunomodulatory activity of PO-DNA. In contrast, HLA-DRA and hBD-2 promoter activation can be induced by liposome-encapsulated PS-DNA in a CG sequence-independent manner, depending on the CpG-DNA species. Our observations demonstrate that, when encapsulated with a proper liposome in the immune system, natural PO-DNA has the potential to be a useful therapy for the regulation of the innate immune response.

• BMB Reports
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• v.34 no.1
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• pp.15-20
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• 2001

One of the innate immune reactions in invertebrates is the pro-phenoloxidase (pro-PO) activation system that is involved in the generation of superoxide, melanin synthesis, and the subsequent sequestration of foreign matter entering the hemocoel of the invertebrates. However, the molecular mechanism of this biological reaction is still obscure. To expand our understanding of the biological roles of the pro-PO activation system in invertebrates, we performed a yeast two-hybrid screening by using three regions of pro-PO as bait and a yeast two-hybrid cDNA library from Tenebrio molitor larvae as prey We isolated a novel partial cDNA clone that encodes a glycine-rich protein that interacted with the active phenoloxidase (termed phenoloxidase interacting protein, POIP). POIP consists of two domains: One is an N-terminal unique domain and the other is a C-terminal glycine-rich domain. The C-terminal glycine-rich domain showed sequential homology with those of insect antifungal proteins. Also, the yeast two-hybrid screen in a reverse orientation (using POIP as bait) yielded PO, suggesting that the PO-POIP interaction is specific. By using a 315 bP PCR fragment of the N-terminal unique region of POIP, we cloned the full-length cDNA of POIP from the Tenebruo cDNA library constructed by using E. coli injected larvae. The interaction analysis between PO, and a truncated fragment lacking the N-terminal unique region of POIP, indicated that the N-terminal unique region is necessary for interaction between PO and POIP. The expression level of the POIP mRNA is increased by bacterial injection into T. molitor larvae. This suggests that POIP might be engaged in the humoral defense reaction.

• Analytical Science and Technology
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• v.12 no.3
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• pp.260-264
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• 1999

A simple and rapid procedure, called FoLT-PCR(Formamide Low Temperature-Polymerase Chain Reaction) was applied to amplifying DNA directly from various forensic biological evidences including human blood, saliva, hair root, or semen without any DNA preparative steps. We added washing step with non-ionic detergent, 1% Triton X-100, and used Taq DNA polymerase instead of Tth DNA polymerase to amplify 3 STR loci and gender allele simultaneouly. Optimal concentration of formamide and annealing temperature were determined empirically to 8%(v/v), and $48^{\circ}C$ respectively. We also compared this method with standard PCR.

• Journal of Life Science
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• v.13 no.1
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• pp.99-104
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• 2003

Aromatic compounds are of major concern among environmental pollutants due to their toxicity and persistence. To monitor aromatic compounds in a real time with a better sensitivity, a new method of SPR (surface plasmon resonance) based on DNA chip (Biacore 3000) was developed here. It is thought that CapR regulatory protein as a complex with phenol, could bind to their corresponding promoter, Po. Biotinylated DNA oligomers for the promoter was synthesized by PCR and coupled onto streptoavidin-linked CM5-chip. CapR regulatory proteins were purified after cloning their genes in pET21a (+) vector and expressing proteins. The interaction was assessed by the system where the regulatory proteins flowed with or without phenol through the cells of DNA chip. CapR regulatory protein even in the presence of phenol had no response to its promoter, Po, suggesting that other factor(s) might be required for the activation of Po promoter. The present work reveals a promising possibility of the SPR-based DNA chip in monitoring specific environmental pollutants in a real time.

• Toxicological Research
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• v.34 no.4
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• pp.291-296
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• 2018

Chemical carcinogenesis is a multistep process. Genotoxic carcinogens, which are DNA-reactive, induce DNA adduct formation and genetic alterations in target cells, thereby generating mutated cells (initiation). Subsequently, preneoplastic lesions appear through clonal proliferation of the mutated cells and transform into tumors (promotion and progression). Many factors may influence these processes in a dose-dependent manner. Therefore, quantitative analysis plays an important role in studies on the carcinogenic threshold of genotoxic carcinogens. Herein, we present data on the relationship between key carcinogenic events and their deriving point of departure (PoD). Their PoDs were also compared to those of the carcinogenesis pathway. In an experiment, the liver of rats exposed to 2-amino-3,8-dimethylimidazo-(4,5-f)quinoxaline (MeIQx) was examined to determine the formation of MeIQx-DNA adducts, generation of mutations at LacI transgene, and induction of preneoplastic glutathione S-transferase placental form (GST-P)-positive foci and tumors (benign and malignant). The PoDs of the above key events in the carcinogenicity of MeIQx were increased as the carcinogenesis advanced; however, these PoDs were lower than those of tumor induction. Thus, the order of key events during tumor induction in the liver was as follows: formation of DNA adducts ${\ll}$ Mutations ${\ll}$ GST-positive foci (preneoplasia) ${\ll}$ Tumor (adenoma and carcinoma). We also obtained similar data on the genotoxic and carcinogenic PoDs of other hepatocarcinogens, such as 2-amino-3,8-dimethylimidazo(4,5-f)quinoline. These results contribute to elucidating the existence of a genotoxic and carcinogenic threshold.

• BMB Reports
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• v.44 no.11
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• pp.758-763
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• 2011

Immunostimulatory CpG-DNA targeting TLR9 is one of the most extensively evaluated vaccine adjuvants. Previously, we found that a particular form of natural phosphodiester bond CpG-DNA (PO-ODN) encapsulated in a phosphatidyl-${\beta}$-oleoyl-${\gamma}$-palmitoyl ethanolamine (DOPE) : cholesterol hemisuccinate (CHEMS) (1 : 1 ratio) complex (Lipoplex(O)) is a potent adjuvant. Complexes containing peptide and Lipoplex(O) are extremely useful for B cell epitope screening and antibody production without carriers. Here, we showed that IL-12 production was increased in bone marrow derived dendritic cells in a CpG sequence-dependent manner when PO-ODN was encapsulated in Lipoplex(O), DOTAP or lipofectamine. However, the effects of Lipoplex(O) surpassed those of PO-ODN encapsulated in DOTAP or lipofectamine and also other various forms of liposome-encapsulated CpG-DNA in terms of potency for protein antigen-specific IgG production and Th1- associated IgG2a production. Therefore, Lipoplex(O) may have a unique potent immunoadjuvant activity which can be useful for various applications involving protein antigens as well as peptides.

• Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.5.1-5.8
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• 2018

Stimulator of interferon gene (STING) is induced by various inflammatory agents, such as lipopolysaccharide and microbial pathogens, including virus and bacteria. In this study, we obtained a full-length cDNA of a STING homolog from olive flounder using rapid amplification of cDNA ends PCR technique. The full-length cDNA of Paralichthys olivaceus STING (PoSTING) was 1442 bp in length and contained a 1209-bp open reading frame that translated into 402 amino acids. The theoretical molecular mass of the predicted protein sequence was 45.09 kDa. In the PoSTING protein, three transmembrane domains and the STING superfamily domain were identified as characteristic features. Quantitative real-time PCR revealed that PoSTING expressed in all the tissues analyzed, but showed the highest level in the spleen. Temporal expression analysis examined the significantly upregulated expression of PoSTING mRNA after viral hemorrhagic septicemia virus (VHSV) stimulation. In contrast, no significant changes in the PoSTING expression were detected in Edwardsiella tarda-challenged group compared to the un-injected control. The expression of P. olivaceus type I interferon (PoIFN-I) was also highly upregulated upon VHSV challenge. These results suggest that STING might be involved in the essential immune defense against viral infection together with the activation of IFN-I in olive flounder.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.4
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• pp.808-822
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• 2014

넙치 (Paralichthys olivaceus)로부터 elastase-like serine protease (PoElSp)를 암호화하는 cDNA를 클로닝하여 그 서열을 분석한 결과, PoElSp 유전자는 269 아미노산을 암호화하는 978염기쌍으로 구성되었다. PoElSp 유전자의 조직 특이적 발현 양상을 RT-PCR법으로 조사한 결과, 간, 비장 및 소장에서 그 발현이 크게 나타났다. lipopolysaccharide (LPS)로 인위적 세균감염을 유도한 후, 1시간째에 콩팥에서, 3시간째에는 근육에서, PoElSp 유전자의 발현이 크게 증가하였다. 또한, 이 유전자의 발현은 비장에서 LPS 주입 후 1-24시간동안 점차로 증가하였다. pro-mature PoElSp (proPoElSp)에 해당하는 cDNA를 pET32a 벡터 시스템을 이용하여 대장균에서 발현시켰다. 이 재조합 proPoElSp 단백질의 활성은 gelatin zymography 방법과 합성형광 Z-Phe-Arg-AMC의 분해법을 이용하여 측정하였다. 단백질 분해효소 활성을 위한 최적 pH는 7.5였다. 실험결과들을 종합하면, PoElSp 단백질은 면역 반응에서 중추적 역할을 하리라 판단된다.

• Mycobiology
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• v.44 no.4
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• pp.283-290
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• 2016

A double-stranded RNA (dsRNA) mycovirus was detected in malformed fruiting bodies of Pleurotus ostreatus strain ASI2792, one of bottle cultivated commercial strains of the edible oyster mushroom. The partial RNA-dependent RNA polymerase (RdRp) gene of the P. ostreatus ASI2792 mycovirus (PoV-ASI2792) was cloned, and a cDNA sequences alignment revealed that the sequence was identical to the RdRp gene of a known PoSV found in the P. ostreatus strain. To investigate the symptoms of PoV-ASI2792 infection by comparing the isogenic virus-free P. ostreatus strains with a virus-infected strain, isogenic virus-cured P. ostreatus strains were obtained by the mycelial fragmentation method for virus curing. The absence of virus was verified with gel electrophoresis after dsRNA-specific virus purification and Northern blot analysis using a partial RdRp cDNA of PoV-ASI2792. The growth rate and mycelial dry weight of virus-infected P. ostreatus strain with PoV-ASI2792 mycovirus were compared to those of three virus-free isogenic strains on 10 different media. The virus-cured strains showed distinctly higher mycelial growth rates and dry weights on all kinds of experimental culture media, with at least a 2.2-fold higher mycelial growth rate on mushroom complete media (MCM) and Hamada media, and a 2.7-fold higher mycelial dry weight on MCM and yeast-malt-glucose agar media than those of the virus-infected strain. These results suggest that the infection of PoV mycovirus has a deleterious effect on the vegetative growth of P. ostreatus.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.245.1-245
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• 1996

No Abstract, See Full Text