• Environmental Analysis Health and Toxicology
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• 제15권3호
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• pp.69-80
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• 2000

ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

• 미생물학회지
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• 제13권3호
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• pp.123-137
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• 1975

Sexual reproduction of paramecia have been accomplished through conjugation between individuals which have opposite mating type substances on their cilia when they were starved. Using selfing clone in which mating takes place, I examined whether a mating type change in indicidual cells required new protein and new mRNA synthesis or not and also shether there is a precursor relationship between both of the complementary mating type substances in their synthetic pathway. I found that 1. Mating type change needs new protein(s) and new mRNA synthesis. 2. Mating type substances are synthesized sequentially from mating type XIII to XIV 3. There might be a common precursor pool from which the mating type XIII substnace is synthesized and then complementary mating type XIV is fromed by addition of small group to the mating type XIII substance.

• 미생물학회지
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• 제21권4호
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• pp.197-206
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• 1983

For the purpose of investigating the effect of nalidixic acid on the nucleic acid synthesis in chloroplast isolated from Chlorella ellipsoidea, cells were cultured in the media treated with nalidixic acid(20ppm) for 5 days. Aliquots cells were taken out at the inoculation and at intervals during the culture and growth rate of Chlorella cells measured. After extraction of nucleic acids in chloroplast isolated from these cells, their contents were analyzed by the base composition and the effect of nalidixic acid on the nucleic acid synthesis interpreted to compare with those of the control. 1. It was showed that the inhibitory concentration affected by nalidixic acid on the growth of Chlorella cells were 20ppm. 2. Because nalidixic acid had depressed the DNA replication in isolated chloroplast as well as whole cell system, these contents were markedly decreased in comparison with those of the control. 3. In the isolated chloroplast as well as in the whole cell system, nalidixic acid was decreased contents of base in the RNA by preventing RNA transcription.

• 생명과학회지
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• 제7권3호
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• pp.180-185
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• 1997

Methylelaiophylin은 gram양성균에 대하여 광범위한 항균활성을 보이며, 특히Bacillus subtilis에서 superoxide redicals을 발생하여 항균활성을 나타낸다. B. subtilis에 대한 항균활성은 wild type strain보다 mutant strain인 rec$^{-}$에 대하여 더민감하며, 이러한 항균력은 항산화제인 dithiothreito에 의하여 현저히 감소되었다. 또한 항균력은 세포내 RNA합성보다 DN합성에 효과적으로 작용하였다. 이러한 결과들은 methylelaiophylin의 항균활성이 세포내에서 발생한 활성산소에 의하여 기인한 것임을 나타낸다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.116-116
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• 2019

Thalictrum rochebrunianum var. grandisepalum (TRG) is a Korean endemic plant, and it is widely used for edible, medicinal, landscape materials. In this study, we examined the protein and mRNA expression levels of MITF, tyrosinase, TRP-1 and TRP-2 by TRG extract (TRGE) in IBMX-treated melanocytes to evaluate the possibility of using TRG as a whitening material. IBMX were reported as melanin synthesis enhancers. It could increase intracellular melanin synthesis by activation of the microphthalmia-associated transcription factor (MITF) signaling pathway. TRGE did not show cytotoxicity at concentrations below $100{\mu}g/ml$ in B16F10 cells. TREG dose-dependently inhibited protein and mRNA levels of MITF, tyrosinase, TRP-1 and TRP-2. Therefore, we suggest that TRGE is an important natural resource for cosmetic raw materials for whitening function.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.238.1-238.1
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• 2003

Hepatic stellate cells (HSC) and the derived myofibroblasts are known to play a central role in liver fibrogenesis. Rhus verniciflua Strokes (RVS) has traditionally been used in Korea herbal medicine for a stomachic tonic. In this study, we observed the effect of RVS acetone extract (Ra) and its five major components on the proliferation, the collagen synthesis, and hepatic fibrosis related proteins mRNA levels in HSC-T6 cells which is a fully activated rat hepatic stellate cell line. Ra inhibited the proliferation and decreased the content of collagen in the HSC-T6 cells. (omitted)

• 한국미생물·생명공학회지
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• 제39권1호
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• pp.93-96
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• 2011

대장균의 16S rRNA 염기 중 진화적으로 매우 보존되어 있는 B2c 인터브리지의 구성요소 중 하나인 C770염기에 치환을 일으키면 단백질 합성이 저하되는 것으로 알려져 있다. 이 연구에서는 770 위치에 C에서 G로 염기치환(C770G)된 16S rRNA의 기능을 회복시키는 이차복귀돌연변이(secondsite revertant)를 얻기 위해 16S rRNA를 암호화하는 DNA 부분에 무작위로 염기치환을 유발시켜, 재조합 리보솜이 번역하는 CAT mRNA로부터의 단백질 합성능력이 향상된 클론을 선별하였다. 이 실험으로 C770G 염기치환을 가진 변이체 리보솜의 단백질 합성능력을 일부 회복시키는 하나의 이차복귀돌연변이체를 획득하였으며, DNA 염기분석을 통하여 C569G와 U904C 염기치환을 가진 것을 확인하였다. 이러한 연구결과를 이용하여 770 염기가 단백질 합성 과정에서 16S rRNA의 어떤 다른 부분과 결합을 하는지, 또한 그러한 결합으로 이루어지는 구조가 가지게 되는 기능은 무엇인지 등에 대한 리보솜의 구체적인 단백질 합성기작 연구에 도움이 될 것으로 기대한다.

• 미생물학회지
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• 제24권3호
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• pp.276-287
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• 1986

ChIarella elliPsoidea를 rifampicin이 함유된 M4N 배지에 7일간 배양하였다. 배양기간 동안에 일정량 세포를 수확하여 생장율을 측정하였다. 이들 세포에서 분리된 엽록체로 부터 핵산과 RNA polymerase를 추출하여 함량을 염기별로, 분석, 활성도를 측정하여 핵산 합성에 비치는 rifampicin의 효과를 대조구와 비교하며 분석하였다. 생장 억제 효과를 나타내는rifampicin의 농도는 80ppm 이였다. Whole cell system과 분리한 엽록체에서의 DNA함량은 대조구에 비해 각각 70%, 60%의 감소를 나타내였다. Rifampicin은 RNA 염기 함양도 whole cell system에서는 46% 억제되었고 분리한 엽록체에서는 77% 저해효과가 관찰되었다. Rifampicin에 의한 RNA polymerase 활성도는 whole cell system에서는 10% 감소, 분리한 엽록체에서는 42% 억제를 나타내었다.

• 생명과학회지
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• 제8권2호
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• pp.119-125
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• 1998

dsRNA결합인자인 RBF단백질을 정제하여 이의 단일 또는 이중선의 RNA 또는 DNA 와의 결합도를 측정하였다ㅓ. RBF단백질은 이들과 각각 반응시켜 그 결합도는 SDS-PAGE에 의하여 비교관찰하였다. RBF단백질은 dsRNA와은 강한 결합력을 나타낸 반면 기타의 핵산구조에 대해서는 이러한 결과를 나타내지 못하였다. 인산화 실험의 결과, RBF단백질은 poly(I) : poly(C)의 존재하에서 사람 도는 쥐 모두로 부터의 PKR 효소의 자가인산화를 유사한 방식으로 억제하였다. 이는 다른 종류의 진핵세포생물에서 단백질합성조절을 위한 PKR과 RBF가 유사한 경쟁적 관련성을 유지하면서 존재함을 시사하고 있다.

• Journal of Microbiology
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• 제38권3호
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• pp.145-149
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• 2000

GroEL is a typical molecular chaperone. GroEL synthesis patterns at various culture temperatures in Escherichia coli were investigated in this study. No significant differences in the amount of GroEL produced from the chromosome were found at 30 and 37$^{\circ}C$. However, GroEL production increased 3.4-fold at 42$^{\circ}C$. GroEL synthesis was not transient but continuous at 42$^{\circ}C$, although most heat shock gene expression is known to be transient. To understand the role of the groEL structural gene, a groE promoter-lacZ fusion was constructed. Interestingly , while transcriptional fusion is not thermally inducible, it is inducible by ethanol, suggesting that the secondary structure of the groEL transcript is involved in thermal regulation of the groEL gene. Secondary structures of groE mRNA at 37 and 42$^{\circ}C$ were compared using the computer program RNAdraw. Distinct structures at the two temperatures were found, and these structures may be related to a high level of GroEL expression at 42$^{\circ}C$.