• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.47-47
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• 2001

The neuropeptide vasopressin (VP) is a nine- amino acid hormone synthesized as preprohormone in the cell bodies of hypothalamic magnocellular neurons. The tumor in magnocellular neurons of the hypothalamus is associated with disfunctions of the cell bodies, leading to the diabetes insipidus. In order to study with the diabetes insipidus caused by a defect in VP synthesis and its secretion, we have produced the transgenic mice regulated by vasopressin promoter inserted to SV40 T antigen coding sequence (pVPSV.IGR2.1). One transgenic line expressing high levels of SV40 T antigen was propagated. The founder and all transgene positive adult animals have appeared with shorten mortality or apparent phenotypic abnormalities, including immune complex disease, and eventually die between 4 and 8 months of age. The mRNA and protein of SV40T antigen transgene were detected in brain of fetus as well as in brain, spleen, lung and lymph node in moribund at the age of 20 weeks. Histological analysis of transgenic mice showed that tumor developed in brain similar to primitive neuroectodermal tumors (PNET) in man. We also detected lymphomas in spleen and lymph node, and consequent tumor formation in various tissues of the transgenic mice. In pVPSV.IGR2.1, 21% mice showed brain tumor (PNET) at 5 weeks and 100% mice showed brain tumor after 15 weeks. In addition, Expression of apoptosis related genes (Bcl-28 & Bax) was increased over their age in mice with PNET as compared to control mice. Apoptosis related gene expression might be deregulated in mice with brain tumor. However, transgenic mice were not developed with the diabetes insipidus. These mice represent the first disease model to exhibit primitive neuroectodermal tumor in brain, as well as a unique model system for exploring the cellular pathogenesis of lymphomas.

• Journal of Applied Biological Chemistry
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• 제54권1호
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• pp.56-62
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• 2011

Tyrosinase 저해활성화 반응에 대한 polyhydroxy 치환된 flavone 유도체(1-25) 중, hydroxyl-치환기($R_1-R_9$)들의 역할을 이해하기 위하여 Free-Wilson 분석과 tyrosinase (PDB ID: Deoxyform (2ZMX) 및 Oxy-form; 1WX2)의 활성화 지점에 대한 분자도킹이 연구되었다. Free-Wilson 분석으로부터 $R_1-R_9$ 치환기중에서 $R_1$=hydroxyl 치환기가 tyrosinase 저해활성에 가장 큰 영향을 미치고 있음을 알았다. 기질분자의 hydroxyl 치환기들과 tyrosinase의 반응점 내 아미노산 잔기들 사이의 수소결합들은 안정한 기질-수용체 착 화합물을 형성하는데 기여하였다. 특히, 수소결합성에 기초한 비경쟁적 저해활성화 반응은 기질분자의 hydroxyl 치환기들과 tyrosinase의 반응점 내 peroxide 산소원자(Per404) 사이의 수소결합을 경유하여 일어날 것임을 제안하였다.

• 한국수산과학회지
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• 제19권5호
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• pp.477-484
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• 1986

The interaction of myofibrillar protein with lipid or oxidized lipid was considered to be mostly contributing to the drop of digestibility of fish meat products. The digestibility of myofibrillar protein was $92.11\%$ for flounder and $88.04\%$ for hairtail fish, repectively, and as a rule it decreased as both the amount of lipid and reaction time increased. It also decreased with increase in the amount of added linoleate and oxidized linoleate. However, when the reaction continued for 6 hours or more the digestibility rather increased, which was provably due to the unfolding of protein structure. The hot air dried hairtail fish showed the lowest C-PER values among all dried fish products. The protein quality of flounder, hairtail fish and their dried ones except hot air dried ones measured by C-PER procedure were superior to that of ANRC casein. DC-PER values of all samples were greater than those of C-PER values and the greater discrepancies were noted in hairtail fish (fatty fish) products which possessed the lower in vitro protein digestibilities. Predicted diegstibilities, which were calculated using amino acid profiles, of all samples except raw ones were overestimated in comparison with in vitro protein digestibilities. From the observations so far, formation of complex of lipids and protein was thought to be the most important factor in lowering protein digestibility of the dried fish meat products.

• 대한핵의학회지
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• 제38권2호
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• pp.198-204
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• 2004

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used $^{18}F$-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. $[^{11}C]Thymidine$ was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of $^{11}C$ and rapid metabolism of $[^{11}C]Thymidine$ in vivo make the radiotracer less suitable for routing use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicing but the image qualify and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog $3'-deoxy-3'-^{18}F-fluorothymidine$ (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. $[^{18}F]FLT$ is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. $[^{18}F]FLT$ PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and $[^{11}C]choline$, which is a new marker for cellular proliferation.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.81-81
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• 1995

It is well known that Src Homology 2(SH2) domain in many intracellular signal transduction proteins is very important. The domain has about 100 amino acid residues and bind phosphotyrosine-containing peptide with high affinity and specificity. Lck SH2 domain is a Src-like, lymphocyte-specific tyrosine kinase. An 11-residue phosphopeptide derived from the hamster polvoma middle-T antigen, EPQp YEEIPIYL, binds with an 1 nM dissociation constant to Lck SH2 domain. And it is known that the phosphotyrosine and isoleucine residues of the peptide are tightly bound by two well-defined pockets on Lck SH2 domain's surface. To investigate the conformational changes during complexation of SH2 domain with phosphopeptide we have performed the molecular dynamics simulation for Lck SH2 domain with peptide and peptide-free form at look in aqueous solution. More than 3000 water molecules were incorporated to solvate Lck SH2 domain and peptide. Periodic boundary condition has been applied in molecular dynamics simulation. Data analysis with the results of that simulation shows that the phosphopeptide makes primary interaction with the Lck SH2 domain at six central residues, The comparison of the complexed and uncomplexed SH2 domain structures in solution has revealed only relatively small change. But the hydrophilic and hydrophobic pockets in the protein surface show the conformational changes in spite of the small structural difference between the complex and peptide-free forms.

• 한국발생생물학회지:발생과생식
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• 제11권3호
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• pp.253-261
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• 2007

Lactadherin은 모유의 유지방구막의 당단백질의 하나로 mucin, butyrophilin과 결합된 복합체이다. 특히 모유중의 mucin과 lactadherin은 출생 직후 면역력이 약한 유아를 병균의 침입으로부터 효율적으로 방어하여 초기 유아의 생존과 성장 및 발달에 매우 중요한 역할을 수행한다. Lactadherin은 유아 설사의 원인이 되는 rotavirus의 번식과 성장을 억제한다. 아울러 이 단백질은 새로운 혈관의 형성을 촉진하는 주요한 단백질로 알려져 있으며, 이 단백질의 결핍이 치매의 발생과 관련되는 것으로 보고되고 있다. 본 연구는 이처럼 중요성이 강조되는 lactadherin에 대한 생화학적 및 생리학적인 연구를 하기 위한 기초연구를 진행하였다. 한국 여성의 유선조직에서 mRNA를 분리하였고, 1.2 kb lactadherin cDNA 유전자를 cloning하여 염기서열과 아미노산 배열을 결정하였다. 이 cDNA를 pET vector에 삽입하여 E. coli에서 43 kD 단백질을 발현시켰으며 Western blot으로 확인하였으며, 이 단백질을 정제하여 토끼에서 항체를 생산하여, 한국 여성의 모유에서 발현되는 70, 55, 46, 30 kD의 band를 확인하였다. 아울러 백인 여성의 lactadherin 유전자와 한국 여성의 정상 및 유방암 조직의 유전자 비교에서 다양한 SNP가 관찰되었고 변이의 다형성이 관찰되었다.

• Molecules and Cells
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• 제22권2호
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• pp.210-219
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• 2006

Dynamin-related protein 2A (AtDRP2A, formally ADL6), a member of the dynamin family, is critical for protein trafficking from the TGN to the central vacuole. However, the mechanism controlling its activity is not well understood in plant cells. We isolated Arabidopsis sec13 homolog1 (AtSeh1) that interacts with AtDRP2A by a yeast two-hybrid screening. AtSeh1 has four WD40 motifs and amino acid sequence homology to Sec13, a component of COPII vesicles. Coimmunoprecipitation and protein pull-down experiments demonstrated specific interaction between AtSeh1 and AtDRP2A. AtSeh1 bound to the pleckstrin homology domain of AtDRP2A in competition with the C-terminal domain of the latter, and this resulted in inhibition of the interaction between AtDRP2A and PtdIns3P in vitro. AtSeh1 localized to multiple locations: the nucleus, the prevacuolar compartment and the Golgi complex. Based on these results we propose that AtSeh1 plays a role in regulating cycling of AtDRP2A between membrane-bound and soluble forms.

• Animal cells and systems
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• 제8권4호
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• pp.307-312
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• 2004

Fast kinetics of transient pH changes and difference spectrum formation have been investigated following mixing of ADP/ATP with partially purified plasma membrane PM-ATPase of the pathogenic yeast Candida albicans in the presence of five nutrients: glucose, glutamic acid, proline, lysine, and arginine and two analogs of glucose: 2-deoxy D-glucose and xylose. Average $H^+$- absorption to release ratio, indicative of population of ATPase undergoing complete hydrolytic cycle, was found to be 0.27 for control. This ratio varied between 0.25 (proline) to 0.36 (arginine) for all other compounds tested, except for glucose. In the presence of glucose, $H^+$- absorption to release ratio was exceptionally high (0.92). While no UV difference spectrum was observed with ADP, mixing of ATP with ATPase led to a large conformational change. Exposure to different nutrients restricted the magnitude of the conformational change; the analogs of glucose were found to be ineffective. This suppression was maximal in the case of glucose (80%); with other nutrients, the magnitude of suppression ranged from 40-50%. Rate of $H^+$- absorption, which is indicative of E~P complex dissociation, showed positive correlation with suppression of conformational change only in the case of glucose and no other nutrient/analog. Mode of interaction of glucose with plasma membrane $H^+$-ATPase thus appears to be strikingly distinct compared to that of other nutrients/analogs tested. The results obtained lead us to propose a model for explaining glucose stimulation of plasma membrane $H^+$-ATPase activity.

• 미생물학회지
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• 제36권2호
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• pp.97-102
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• 2000

녹장균(Metarhizium ansiopliae)을 생물살충제로서 활용할 목적으로 녹강균의 균사생육 및 포자형성에 미치는 환경요인과 균사외 분비 효소 활성에 대하여 조사였다. M. anisopliae DGUM35001의 균사 생장을 보여주었으며, 공중균사는 SDPY 사용시 가장 우수하엿다. 최소배지로 Czapek-Dox 한천배지를 사용하여 탄소원 이용성 실험의 결과, 단당류에서 glucoserk 이당류에서 sucrose가 가장 우수한 탄소원이었다. 고분자 물질로 chitin 사용시 우수한 균사 생육을 보여주었다. 유기질소원으로 bacto-peptone과 soytone아 무기질소원으로 urea와 ammonium phosphate가 우수한 균사생육을 나타내었으며, 아미노산으로 serine 첨가시 가장 우수한 균사 생육을 나타내었다. Starch배지를 사용하였을 때 가장 우수한 포자형성의 결과를 얻었다. 액체배양후 군사를 제거한 상등액을 조효소액으로 사용시 analyase와 prorease 효소 활성이 우수하였다. 그러나,;ipase와 chitinase 효소활동은 상대적으로 낮았다.

• 정보처리학회논문지D
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• 제19D권1호
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• pp.21-28
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• 2012

모노머 단백질의 상호작용 사이트 예측은 기능을 알지 못하는 단백질에 대해서 이것과 상호작용하는 단백질로부터 기능을 예측하거나 단백질 도킹을 위한 검색 공간의 감소에 중요한 역할을 한다. 그러나 상호작용사이트 예측은 대부분 단백질 상호작용이 세포 내에서 순간적 반응에 일어나는 약한 상호작용으로 실험에 의한 3차원 결정 구조 식별의 어려움이 따르며 이로 인해 3차원의 복합체 데이터가 제한적으로 양산된다. 이 논문에서는 모노머 단백질의 3차원 패치 계산을 통하여 구조가 알려진 복합체의 상호작용사이트와 비상호작용사이트에 대한 패치 속성을 추출하고 이를 기반으로 Support Vector Machine (SVM) 분류기법을 이용한 예측 모델 개발을 제시한다. 타겟 클래스의 데이터 불균형 문제 해결을 위해 under-sampling 기법을 이용한다. 사용된 패치속성은 2차 구조 요소와 아미노산 구성으로부터 총 9개가 추출된다. 147개의 단백질 복합체에 대해서 10 fold cross validation을 통해서 다양한 분류모델의 성능 평가를 하였다. 평가한 분류 모델 중 SVM은 92.7%의 높은 정확성을 보이고 이를 이용하여 분류 모델을 개발하였다.