• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.23-25
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• 2008

Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.

• 약학회지
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• 제44권2호
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• pp.197-203
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• 2000

The enzymatic properties of $\beta$-galactosidases from Aspergillus oryzae, bovine liver and Saccharomyces pragilis have been studied using enzyme-linked lectin assay based on the RC $A_{120}$ and BS-II lectins which specifically bind to terminal galactose and GlcNAc residue, respectively. Asialofetuin, a monomeric glycoprotein with approximately 48 kDa in molecular weight, was used as a substrate. This glycoprotein contains three N-linked triantennary complex type carbohydrate chains with each of which terminating in Ga1$\beta$P1 longrightarrow4G1cNAc (74%). Their optimal pHs were 3.5 and 6.5 (A. oryzae), and 3.5~5.5 (bovine liver and S. fragilis) at 37$^{\circ}C$ during 24 hrs, and the effective concentrations were 0.9, 2.9, and 1.7 mg/ml, respectively The enzyme from A oryzae requires 100 mM N $a^{+}$ or $K^{+}$, while the enzyme from bovine liver requires $Ba^{2+}$ for activity. However all of the three $\beta$-galactosidases were inactivated by SDS and C $u^{2+}$. These results indicate that the hydrolysis of glycoprotein such as asialofetuin depends on the reaction conditions of $\beta$-galactosidases and some metal ions. ions.

• Applied Biological Chemistry
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• 제42권4호
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• pp.304-309
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• 1999

식용버섯인 팽이버섯(Flammulina velutipes)으로부터 적혈구 응집능력을 갖는 렉틴(flammulina velutipes lectin, FVL) FVL-1과 FVL-2을 정제하였다. FVL-1과 FVL-2의 분자량은 각각 10.6 kDa과 37 kDa으로 추정되었다. FVL-2는 사람적혈구의 경우 모든 혈액형에서 응집현상을 나타내었으나, FVL-1은 O형의 적혈구에 대하여 높은 상대활성도를 나타내었다. 렉틴의 hemagglutination inhibition test 결과 FVL-1과 FVL-2는 fetuin, bovine submaxillary mucin, asialofetuin, porcine stomach mucin에 의해 적혈구 응집력이 저해되었다. FVL-1은 1.56 mM $Cu^{2+}$에서 적혈구 응집력이 저해되었으며, $Mg^{2+}$, $Mn^{2+}$, $Ca^{2+}$, $Fe^{2+}$ 등에서도 저해되었다. 반면 FVL-2는 금속 이온에 대한 저해가 나타나지 않았다. pH 안정성에 있어서 FVL-1은 pH $5{\sim}11$에서 안정하였으며, FVL-2는 pH 4까지의 범위에서 안정하였다. 온도 안정성에 있어서는 FVL-1과 FVL-2 각각 $55^{\circ}C$, $45^{\circ}C$까지 안정하였다. FVL-1은 단백질이었으며 FVL-2는 당 단백질이었다.

• IMMUNE NETWORK
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• 제13권5호
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• pp.205-212
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• 2013

Dectin-1, which specifically recognizes ${\beta}$-glucan of fungal cell walls, is a non-Toll-like receptor (TLR) pattern recognition receptor and a representative of C-type lectin receptors (CLRs). The importance of Dectin-1 in innate immune cells, such as dendritic cells and macrophages, has previously been well studied. However, the function of Dectin-1 in B cells is very poorly understood. To determine the role of Dectin-1 in B cell activation, we first investigated whether mouse B cells express Dectin-1 and then assessed the effect of Dectin-1 stimulation on B cell proliferation and antibody production. Mouse B cells express mRNAs encoding CLRs, including Dectin-1, and surface Dectin-1 was expressed in B cells of C57BL/6 rather than BALB/c strain. Dectin-1 agonists, heat-killed Candida albicans (HKCA) and heat-killed Saccharomyces cerevisiae (HKSC), alone induced B cell proliferation but not antibody production. Interestingly, HKSC, HKCA, and depleted zymosan (a selective Dectin-1 agonist) selectively enhanced LPS-driven IgG1 production. Taken together, these results suggest that, during fungal infection, ${\beta}$-glucan-stimulated Dectin-1 may cooperate with TLR4 to specifically enhance IgG1 production by mouse B cells.

• BMB Reports
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• 제46권7호
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• pp.358-363
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• 2013

In this paper, we firstly reported a C-type lectin cDNA clone of 1029 bps from the larvae of A. Pernyi (Ap-CTL) using PCR and RACE techniques. The full-length cDNA contains an open reading frame encoding 308 amino acid residues which has two different carbohydrate-recognition domains (CRDs) arranged in tandem. To investigate the biological activities in the innate immunity, recombinant Ap-CTL was expressed in E. coli with a 6-histidine at the amino-terminus (Ap-rCTL). Besides acted as a broad-spectrum recognition protein binding to a wide range of PAMPs and microorganisms, Ap-rCTL also had the ability to recognize and trigger the agglutination of bacteria and fungi. In the proPO activation assay, Ap-rCTL specifically restored the PO activity of hemolymph blocked by anti-Ap-rCTL antibody in the presence of different PAMPs or microorganisms. In summary, Ap-rCTL plays an important role in insect innate immunity as an pattern recognition protein.

• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1420-1428
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• 2009

In this study we cloned and characterized a novel lipid-accumulating gene, the oxidized low-density lipoprotein receptor 1 (OLR1), which is associated with lipogenesis. We analyzed the gene structure and detected the mRNA transcriptional expression levels in pig adipose tissues at different months of age (MA) and in different economic types (lean type and obese type) using real-time fluorescence quantitative PCR. OLR1 expression profile in different tissues of pig was analyzed. Finally, we studied the correlation between OLR1 and lipid metabolism related genes including peroxisome proliferator-activated $receptor{\gamma}2$ ($PPAR{\gamma}2$), fatty acid synthetase (FAS), triacylglycerol hydrolase (TGH), CAAT/enhancer binding protein $\alpha$ ($C/EBP{\alpha}$) and sterol regulatory element binding protein-1c (SREBP-1c). Results indicated that the OLR1 gene of the pig exhibited the highest homology with the cattle (84%), and the lowest with the mouse (27%). The signal peptide located from amino acid 38 to 60 and the domain from amino acid 144 to 256 were shared by the C-type lectin family. The expression level of OLR1 in pig lung was exceedingly higher than other tested tissues (p<0.01). In pig adipose tissue, the expression level of OLR1 mRNA increased significantly with growth (p<0.01). The expression level of OLR1 mRNA in obese-type pigs was significantly higher than that of lean-type pigs of the same monthly age (p<0.05). In adipose tissue, the expression of OLR1 correlated with $PPAR{\gamma}2$, FAS and SREBP-1c, but not TGH or C/EBP${\alpha}$. In conclusion, OLR1 was highly associated with fat deposition and its transcription, as suggested by high correlations, was possibly regulated by $PPAR{\gamma}2$ and SREBP-1c.

• 환경생물
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• 제36권2호
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• pp.131-139
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• 2018

기후 변화로 인한 수온의 상승은 어류 서식지에 영향을 미친다. 수온의 변화는 어류 생리 거의 모든 부분에 영향을 미치는 것으로 알려져 있다. 기후 변화에 따른 수온의 상승은 산소 용해도의 감소 및 산소 운반 헤모글로빈의 결합 능력의 감소로 인해 저산소증을 초래할 수 있다. 본 연구는 대서양 연어(Salmo salar) 치어 성장의 최적수온($15^{\circ}C$)보다 고수온($20^{\circ}C$)에 사육 시, 대서양 연어 치어의 건강상태를 평가하기 위해 수행되었다. 평가 방법은 NGS RNAseq 분석방법을 이용하여 생체지표유전자를 개발하고, RT-qPCR 분석을 이용하여 생체지표유전자의 발현양상을 조사하는 것이다. 개발한 생체지표유전자로는 interferon alpha-inducible protein 27-like protein 2A transcript variant X3, protein L-Myc-1b-like, placenta growth factor-like transcript variant X1, fibroblast growth factor receptor-like 1 transcript variant X1, transferrin, intelectin, thioredoxin-like, c-type lectin lectoxin-Thr1-like, ladderlectin-like 및 calponin-1 등이다. 선택된 생체지표 유전자는 NGS RNAseq 분석을 통해 수온변화에 민감하게 발현한 유전자들이며, RT-qPCR 분석을 통한 이들 유전자의 발현 양상은 NGS RNAseq 분석을 통한 발현 양상과 매우 유사하게 나타났다.

• Mycobiology
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• 제38권2호
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• pp.144-148
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• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.213.2-214
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• 2003

Three mistletoe lectins (ML -I, ML -IIU, ML -IIL) have been identified in Europe based on sugar specificities for galactose(Gal) and N-acetyl galactosamine(GalNAc). Korean mistletoe lectins have been known as mainly ML -II type. In previous results, we suggested that there are two lectins, 64 KDa and 60 KDa, in Korean mistletoe lectin (KML -C). (omitted)

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.67-77
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• 2000

심해에서 서식하며 특이한 조직형태를 갖고 있는 꼼치조직에서 cDNA를 제작하여 클로닝을 통해서, 꼼치에서 특이하게 발현하는 유전인자를 검색하였다. 그 결과 62례의 클론이 알려진 유전자에 동질성이 있었는데 이들은 thioesterase가 9례, myosin이 8례, creatine kinase가 7례, skeletal alpha-actin이 6례, parvalbumin b와 ribosomal protein이 각각 5례, type I collagen과 muscle troponin이 각각 3례, dopamine receptor, histatin, 그리고 heat shock protein이 각각 2례, cystatin, lectin, statherin, secretory carrier membrane protein, keratin type I, desmin, chloroplast, muscle tropomyosin, reticulum calcium ATPase, ribonucleoprotein이 각각 1례로 나타났다. 나머지 클론은 동질성이 낮거나 비반복성으로 나타났으며, 이 중 in situ hybridization으로 조직에서 특이하게 발현되는 5종류의 클론을 선택하여 분석하였으며, C 말단 단백질 구조와 특색(motif)을 분석하였다. 5종류의 클론에서 C9O-77은 약 5000bp 크기로 상피조직, 점액조직, 섬유조직 그리고 교원질 조직에서 강한 양성반응을 보이는 세포의 기질단백질로 예상되었다. C9O-116은 약 1500bp 크기로 섬유조직, 상피조직 그리고 점액조직에서 약한 양성반응을 보였고, 근육 다발 주변 부위 세포에서 매우 강한 양성반응을 보이는 막투과성 단백질로 예상되었다. C9O-130은 약 1200bp 크기로 상피조직, 근육조직 그리고 점액조직에서 양성반응을 나타냈으며, 특히 상피조직에서 강한 양성반응을 나타내는 세포내 단백질로 예상되었다. C9O-161은 약 2000bp 크기로 상피조직 과 근육조직 그리고 점액성 섬유조직에서 약한 양성반응을 보였고, 상피세포에서 강한 양성반응을 보였으며, 근육다발을 둘러싸는 섬유성 세포에서도 강한 양성반응을 보이는 세포외 기질단백질로 추측되었다. C9O-171은 약 1000bp크기로 상피조직, 근육조직 그리고 섬유기질 조직에 널리 강한 양성반응을 나타냈으며 교원띠조직에서도 양성반응을 보이는 전사인자로 추측되었다.