• Clinical and Experimental Reproductive Medicine
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• 제32권4호
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• pp.337-346
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• 2005

Objective: The oligosaccharide moieties of glycoproteins and proteoglycans have a vital function in blastocyst differentiation. Concanavalin (ConA), a lectin, is known to bind on the preimplantation embryos, especially on blastocyst. In this study, we investigated whether ConA can modulate the trophoblast development and about the regulating mediator. Also, we investigated whether expansion is enough for hatching procession of the mouse blastocyst. Method: Embryos were collected at 72 h post hCG injection and chemicals were treated after 24 h (96 hr post hCG injection). ConA or calcium ionophore A23187 were exposed to blastocyst and than analysis the developmental process for 48 hr. Intracellular free-$Ca^{2+}$ concentration in trophectoderm was measured with confocal laser microscope after exposing to ConA or calcium ionophore A23187. ConA-pretreated blastocyst exposed to the calcium ionophore A23187 and then analyzed the developmental process. Otherwise ouabain was treated to the blastocyst to block the $Na^+/K^+$-ATPase activity. Results: In contrast to the control blastocyst, the ConA-exposed blastocysts developed beyond the expansion stage with significantly high rate (90.4%) at 12 h post administration. ConA induced an increase the intracellular $Ca^{2+}$ concentration in trophectoderm. Calcium ionophore A23187 also stimulated expansion of blastocyst. Most of the control blastocysts developed to the hatching stage at 144 h post hCG injection. However, strongly 65% of the ConA-exposed embryos were arrested at expanded stage at same time point. The developmental progression rates to hatching stage of both ConA- and calcium ionophore A23187-expose blastocysts were significantly lower than that of the control. However ConA-pretreated embryos developed to the hatching stage like control embryos. Ouabain showed a tendency to delayed the progress to expansion stage but did not inhibit the development to the hatching stage. Conclusion: ConA-mediated expansion is the result of the increase of intracellular free-calcium in blastocyst stage embryo. It is suspected that expansion of the blasocyst is a essential indirect factor in hatching and the calcium may triggering the cellular mechanisms for the both expansion and hatching progression.

• Archives of Pharmacal Research
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• 제14권3호
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• pp.207-216
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• 1991

Pseudixus japonicus agglutinin (PJA) was isolated. And its characteristics were compared with those of concanavalin A (Con A). PJA is a glycopritein composed of 49.3% carbohydrate and 50.7% protein which had relatively high percentages of glutamic acid, aspartic acid and phenylalanine residues. The hemagglutinating activity of PJA was approximately one-eighth of that of Con A when tested with mouse crythrocytes. PJA failed to simulate the proliferation or transformation of human and mouse lymphocytes in contratst to Con A. PJA and Con A showed cytotoxicities against SNU-1 (human stomach cancer cells), SNU-CI (human colon cancer cells) and mouse Sarcoma 180 cells when tested by 3-(4, 5-dimethyl thiazol-2-yl)2. 5-diphenyl tetrazolium bromide (MIT) colorimetric assay. The antitumor activity of the lectin in vivo was also tested in Sarcoma 180 bearing mice. There was no significant difference in prologation of lifc span of the mice after the treatment with PJA and Con A for 10 consecutive days.

• 한국발생생물학회지:발생과생식
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• 제12권3호
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• pp.267-274
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• 2008

포배의 분화는 배아의 착상에 있어 핵심적인 단계로 배아 자체 또는 생식수관에서 유래하는 조절요인의 조절을 받는다. 이들 조절요인과 포배와의 순차적인 신호의 주고 받음은 분화의 중요한 단계로 인식되고 있다. 한편, 포배기 때 자유 칼슘을 통한 신호전달경로가 포배의 분화에 중요한 축의 하나로 제안되어 왔다. Concanavalin A(Con A)가 포배의 자유 칼슘 농도 증감을 유도한다는 것을 밝혀졌으나, 포배 내 자유 칼슘 농도를 변형시켜 부화와 그 이후의 발생을 촉진하는 것으로 알려진 heparin-binding epidermal growth factor-like growth factor(HB-EGF)와는 달리 팽창 이후의 부화를 억제하였다. 따라서 본 연구에서는 착상과정에서 중요한 역할을 하는 것으로 알려진 prostaglandin $E_2(PGE_2)$가 포배의 분화에 관여하는지를 Con A와 연계하여 알아보았다. Con A는 그 처리 시간에 관계없이 1시간 처리군 그리고 계속처리군에서 팽창은 촉진하고 부화는 유의하게 억제하였다. 특히 계속처리군에서 부화율이 1시간 처리군에 비하여 유의하게 감소하였다. 또한, $PGE_2$도 포배 내 자율 칼슘 농도를 증가시켰으나 팽창과 부화를 촉진하지 않았다. 또한, $10{\mu}m\;PGE_2$ 농도에서는 부화가 억제되는 경향을 보였다. 그러나 흥미롭게도 $PGE_2$는 Con A가 처리된 포배의 부화를 촉진하였다. Con A를 전처리한 포배에 $PGE_2$를 처리할 경우 포배 내 자유 칼슘의 농도 증감이 진행됨을 공촛점현미경을 이용하여 분석할 수 있었다. 이러한 결과는 신호물질에 의해 유도된 자유 칼슘 농도의 증감이 신호물질에 따른 각기 다른 칼슘 매개로 활성화되는 신호경로를 조절하는 것을 추정할 수 있다. 또한, 순차적 신호물질 조절에 의한 자유 칼슘의 농도 증감이 포배의 분화에 있어 중요함을 제안한다.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2106-2112
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• 2018

Concanavalin A (ConA) interacts with carbohydrates as a lectin, and recent reports proposed its application for detecting a diversity of viruses and pathogens. Structural studies have detailed the interaction between ConA and carbohydrates and the metal coordination environment with manganese and calcium ions (Mn-Ca-ConA). In this study, ConA was crystallized with a cadmium-containing precipitant, and the refined structure indicates that $Mn^{2+}$ was replaced by $Cd^{2+}$ (Cd-Ca-ConA). The structural comparison with ConA demonstrates that the metal-coordinated residues of Cd-Ca-ConA, that is Glu8, Asp10, Asn14, Asp19, and His24, do not have conformational shifts, but residues for sugar binding, including Arg228, Tyr100, and Leu99, reorient their side chains, slightly. Previous studies demonstrated that excess cadmium ions can coordinate with other residues, including Glu87 and Glu183, which were not coordinated with $Cd^{2+}$ in this study. The trimeric ConA in this study coordinated $Cd^{2+}$ with other residues, including Asp80 and Asp82, for complex generation. The monomer does not have specific interaction near interface regions with the other monomer, but secondary cadmium coordinated with two aspartates (Asp80 and Asp82) from monomer 1 and one aspartate (Asp16) from monomer 2. This study demonstrated that complex generation was induced via coordination with secondary $Cd^{2+}$ and showed the application potential regarding the design of complex formation for specific interactions with target saccharides.

• Journal of Microbiology and Biotechnology
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• 제27권12호
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• pp.2241-2244
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• 2017

The structure of concanavalin A (ConA) has been studied intensively owing to its specific interactions with carbohydrates and its heterometal ($Ca^{2+}$ and $Mn^{2+}$) coordination. Most structures from X-ray crystallography have shown ConA as a dimer or tetramer, because the complex formation requires specific crystallization conditions. Here, we reported the monomeric structure of ConA with a resolution of $1.6{\AA}$, which revealed that metal coordination could trigger sugar-binding ability. The calcium coordination residue, Asn14, changed the orientation of carbohydrate-binding residues and biophysical details, including structural information, providing valuable clues for the development and application of detection kits using ConA.

• 한국동물학회지
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• 제29권3호
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• pp.171-180
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• 1986

단백질 분해효소, neuraminidase 및 EDTA가 아메바의 배양기표면 흡착, 세포표면의 미세구조 및 생화학적 조성에 미치는 영향을 concanavalin A(con A) cytochemistry 및 SDS PAGE에 의해 조사하였다. Con A cytochemistry에 의해 세포표면 바깥쪽의 filamentous(F)층과 안쪽의 amorphous(A)층이 쉽게 구분되었다. Neuraminidase로 처리한 아메바는 대조군에 비해 용기표면 흡착성과 펴짐이 증가하였으며 A층과 F층에 더 많은 con A결합부위가 노출되었다. Trypsin 및 proteinase K로 처리한 아메바는 각각 12시간, 48시간동안 용기표면에 부착하지 못하였으며, proteinase K의 처리는 A층의 con A결합부위 및 모든 glycoprotein을 제거시키는 효과를 낳았으며, trypsin은 세포막의 PAS염색물질에는 아무런 변화를 초래하지 않았으나 A층과 F층의 con A결합부위를 제거하였다. 이들 효소 및 EDTA처리에 의해 세포 표면의 mucopolysaccharide 일부가 분리되었다. 아메바를 monovalent con A로 처리하였을 때도 아메바는 용기표면에 부착하지 못하고 cytolysis되었다. 이상의 결과로 아메바의 용기표면 흡착에는 세포막의 glycoprotein과 A층의 mucopolysaccharide간의 상호작용에 의해서 이루어지는 것으로 보인다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.323-323
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• 2022

Jack bean [Canavalia ensiformis (L.)], belonging to the Leguminosae family has been frequently used in edible and medicinal plants in Asian countries. Jack beans are high in protein which is approximately 30%. Concanavalin A (Con A) is a major protein of Jack bean and belongs to the family of legume lectins. It has inhibitory effect on hepatocellular carcinoma by inducing autophagy. However, Con A negatively affects nutrient utilization by other mechanisms. It binds to the glycoproteins and glycolipids of the digestive tract mucosa, inhibits the activity of the enzymes of the brush border of the enterocytes. In order to use Jack bean young seedpods, they are restricted to 'young pods (soft, pre-swelling)' according to the 'Food Code' (Ministry of Food and Drug Safety). Therefore, in this study, we investigated the quantitative change of Con A across developmental stages of Jack bean pods. Biological samples consisted of Jack bean pods and seeds in 7 stages of development. The expression pattern of Con A mRNA was monitored by quantitative reverse transcription PCR (RT-qPCR). Expression of Con A proteins was analyzed by western blotting. The expression of Con A mRNA and protein in the seeds tended to increase gradually as the seeds expanded. However, in pods, they were much less than in seeds. As the expression of Con A mRNA and protein increases as the pods thicken, it is predicted that Con A synthesis increases when the thickness growth of the pod begins after the length growth of the pod is completed. Since the expression of Con A in the pods and seeds in very low when the pods are about 2 cm, therefore 2 cm pods seem appropriate when using 'young pods'. It is also necessary to study other proteins in Jack bean, such as Urease and Canavalin. These studies will serve as the basis for processing Jack bean.

• 약학회지
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• 제43권2호
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• pp.208-213
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• 1999

The effects of five lupane-triterpenoids from leaves of two Acanthopanax spp., chiisanogenin, chisanoside and $22{\alpha}-hydroxychiisanogenin$, acakoreoside A and acantrifoside A on the mitogen-induced proliferation were investigated in vitro. T cell proliferation (TCP) to concanavalin A (Con A) and the B cell proliferation (BCP) to lipopolysaccharide (LPS) were increased by chiisanogenin. TCP to Con A was significantly increased by chiisanoside and acankoreoside A, but not affected by chiisanogenin, $22{\alpha}-hydroxychiisanogenin$ and acantrifoside A, BCP to LPS was significantly increased by acankoreoside A and acantrifoside A, and slightly increased by chiisanoside, chiisanogenin and $22{\alpha}-hydroxychiisanogenin$.

• 대한수의학회지
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• 제26권2호
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• pp.245-249
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• 1986

The present study has been carried out to investigate the optimal condition on the blastogenesis of guinea pig lymphocytes. A microculture system in conjunction with a semiautomatic multiple sample harvester(SAMSH) was used to study the in vito optimal condition of guinea pig lymphocytes. Data were presented to show many variables that are Involved in studying the responses of guinea pig lymphocyte in a microculture system to the stimulation of Concanavalin A(Con A) and lipopolysaccharide (LPS). Analysis indicated that the conditions for optimal Con A as measured by incorporation of $^3H$-TdR include : (1) use of RPMI-1640 as culture medium, (2) use of $6{\mu}g$ of Con A, per culture, (3) use of $1{\times}10^6$ cells per culture. Conditions for optimal stimulation with LPS mitogen were similar to those used for Con A.

• 한국약용작물학회지
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• 제8권4호
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• pp.291-296
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• 2000

구기자나무의 부위별 물추출물이 LPS (lipopolysaccharide) 및 Con A (concanavalin A)에 의한 마우스의 비장세포 증식능에 미치는 영향을 시험한 결과 부위별 면역 활성중 과실에서 의 No mil 처리구에서는 $0.1mg/ml{\sim}0.5mg/ml$ 농도에서, LPS 처리구에서는 $0.01mg/ml{\sim}0.1mg/ml$의 농도에서 B-cell (체액성 면역)의 분열증식을 촉진시켰다. 잎과 뿌리는 LPS 처리구에서 0.1mg/ml 까지 비장세포의 분열증식을 촉진시켰으며 Con A 처리구에서는 T-cell (세포성 면역)의 증식효과가 없었다.