• 대한의생명과학회지
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• 제9권4호
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• pp.195-201
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• 2003

Aromatic hydrocarbons are of major concern among genotoxic chemicals due to their toxicity and persistence. Some microorganisms can utilize aromatic hydrocarbons as carbon and energy sources by inducing expression of catabolic operon(s). The XylR regulatory protein activates transcription of the catabolic enzymes to degrade BTEX (benzene, toluene, ethylbenzene, and xylene) from its cognate promoters, Pu and Ps upon exposure of the cells to the aromatic hydrocarbons. The activity of XylR on the promoters was previously monitored using luciferase luc reporter system. The xylR, its promoter Pr and the promoter Po for the phenolic compound catabolic operon were introduced upstream of firefly luciferase luc in the pGL3b vector to generate about 7.1 kb of pXRBTEX. Here E. coli harboring the plasmid was freeze-dried under various conditions to fin,d optimal conditions for storage and transport. The cell viability and luciferase activity were maintained better, when the cells were freeze-dried at -7$0^{\circ}C$ in the addition of the 10% skim milk or 12% sucrose. However, coaddition of protectants such as 10% skim milk plus 10% glucose or 12% sucrose plus 10% glucose, resulted in much better viability and bioluminescence activity compared with the effect of single addition of each protectant. In addition, it was shown that the freeze-dried cells maintained almost intact bioluminescent activities and cell viability for at least 1 week after freeze-drying. This work demonstrated that the properly freeze-dried recombinant bacterial cells could be utilized as a whole-cell biosensor for simple and rapid monitoring of BTEX in the environment.

• 한국환경성돌연변이발암원학회지
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• 제24권4호
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• pp.163-170
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• 2004

CYP1B1 enzyme metabolize PAHs and estradiol. CYP1B1 metabolize estradiol to 4-hydroxyestradiol that is considered as carcinogenic metabolite. Luciferase activity was induced about 20 folds over that control by 1 nM TCDD (2,3,7,8-tetrchlorodibenzo-p-dioxin) and these inductions were dose-dependent. Recent industrialized society, human hasbeen widely been exposed to widespread environmental contaminants such as PAHs (polycyclic aromatic hydrocarbon) that are originated from the incomplete combustion of hydrocarbons. PAHs are known to be ligands of the AhR (aryl hydrocarbon receptor). Induction of cytochrome P4501B1(CYP1B1) in cell culture is widely used as a biomarket for PAHs. Therefore we have studied the effect of PAHs in the human breast cancer cells MCF-7 to evaluate bioactivity of PAHs. Cytochrome P4501B1(CYP1B1) is known to be inducible by xenobiotic compounda such as policyclic aromatic hydrocarbon (PAH) and dioxins such as 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). And these induction of CYP1B1 is also regulated by many categories of chemicals. In order to investigate the effects of several chemicals on CYP1B1 gene expression in luciferase gene, and then transfected into these cells. After treatment of chemicals, the luciferase activity was measured. We examined effects of PAHs on the CYP1B1-lucifrease reporter gene and CYP1B1 mRNA level. Benzo(k)fluoranthene showed strong response to CYP1B1 promoter activity stimulation, and also CYP1B1 mRNAs increase in MCF-7 cells in a concentration-dependent manner. flvonoids such as genistein decreased B(k)F induced luciferase activity at low concentration. it exhibited stimulatory effect at high concentration.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.341-344
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• 2005

The expression of the glutathione S-transferase (GST), whose induction accounts for antioxidant defense system, is regulated by activation of CCAAT/enhancer binding protein ${\beta}$ ($C/EBP{\beta}$), Sick house syndrome (SHS) presents healthy damage owing to the indoor environment of a building. Toluene has been implicated in one of the important causes of SHS. The present study investigated the effects of toluene treatment on the induction of GSTA2 gene and its mechanism. H411E cells treated with toluene, and GSTA2 expression was determined by immunoblot analysis. The translocation of $C/EBP{\beta}$ was assessed by immunocytochemical assays. $C/EBP{\beta}$ DNA binding activity was determined by electrophoretic mobility shift assays. The role of the C/EBP binding site in the induction of the GSTA2 gene was assessed by luciferase reporter-gene activity. Toluene induced GSTA2 protein expression. In toluene-treated cells, $C/EBP{\beta}$ translocated to the nucleus and bound to the consensus sequence of C/EBP (TTGCGCAA). Toluene treatment increased luciferase reporter-gene activity in cells transfected with the C/EBP-containing regulatory region of the GSTA2 gene. Oxidative stress is believed to play an important role in the induction of GSTA2 gene by toluene This study shows that toluene-induced GSTA2 gene expression is dependent upon nuclear translocation and binding of $C/EBP{\beta}$ to the C/EBP response element in the GSTA2 gene promoter.

• BMB Reports
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• 제46권9호
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• pp.454-459
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• 2013

LRRK2 (leucine-rich repeat kinase 2) has been identified as a gene corresponding to PARK8, an autosomal-dominant gene for familial Parkinson's disease (PD). LRRK2 pathogenic-specific mutants induce neurotoxicity and shorten neurites. To elucidate the mechanism underlying LRRK2 expression, we constructed the LRRK2-promoter-luciferase reporter and used it for promoter analysis. We found that the glucocorticoid receptor (GR) transactivated LRRK2 in a ligand-dependent manner. Using quantitative RT-PCR and Western analysis, we further showed that treatment with dexamethasone, a synthetic GR ligand, induced LRRK2 expression at both the transcriptional and translational levels, in dopaminergic MN9D cells. Dexamethasone treatment also increased expression of ${\alpha}$-synuclein, another PD causative gene, and enhanced transactivation of the ${\alpha}$-synuclein promoter-luciferase reporter. In addition, dexamethasone treatment to MN9D cells weakly induced cytotoxicity based on an LDH assay. Because glucocorticoid hormones are secreted in response to stress, our data suggest that stress might be a related factor in the pathogenesis of PD.

• 동의생리병리학회지
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• 제26권3호
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• pp.344-350
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• 2012

Previously, we showed that Dangguisoo-san (DGSS), an herbal formula that has been traditionally used for the treatment of blood stagnation, is also applicable for inflammatory lung diseases. Activation of Nrf2, an anti-inflammatory transcription factor, and suppression of NF-${\kappa}B$, a pro-inflammatory transcription factor, were suggested as an underlying mechanism. However, the constituents responsible for these activities remain unidentified. To this end, we prepared the water extracts of the 9 constituents of DGSS and tested for their effect on Nrf2 by using an Nrf2-Luciferase reporter cell line and western blot analysis. Results show that Carthamus tinctorius L.(CT), one of the 9 constituents of DGSS, strongly activated Nrf2. Similarly, when measured the effect of the 9 constituents on NF-${\kappa}B$ by using an NF-${\kappa}B$-Luciferase reporter cell line and western blotting for nuclear p65, indicative of activated NF-${\kappa}B$, most constituents were capable of suppressing NF-${\kappa}B$ in various degrees. However, CT and Cyperus rotundus L. (CR) strongly suppressed NF-${\kappa}B$ activity elicited by LPS. Of note, CT activated Nrf2 and suppressed NF-${\kappa}B$ strongly as well. Our results contributes to corroborating the anti-inflammatory effects of DGSS by identifying CT and CR as two major herbs responsible for activating Nrf2 and suppressing NF-${\kappa}B$. These results suggest that CT and CR represent some of the effects of DGSS in the regulation of inflammation.

• 생명과학회지
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• 제19권9호
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• pp.1289-1293
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• 2009

원암단백질로 알려진 Human cervical cancer oncogene (HCCR)은 발암억제 단백질인 p53과 작용하여 다양한 암조직에서 암의 유발을 촉진한다. 그러나, 아직 정확한 발암 유도기전이 알려져 있지 않다. 이러한 의문을 해소하기 위한 일환으로 본 연구에서는 HCCR의 발현이 어떻게 조절되는지를 조사하였다. 이를 위해 먼저 HCCR 5' 쪽의 promoter 영역을 분리하여 Luciferase assay법을 이용하여 K562, HEK293, A549 세포에서 분석하였고, Promoter의 -370에서 -406사이 36bp의 첨가로 promoter활성이 의미 있게 억제됨을 관찰하였다. 또한, 36 bp만을 포함하는 probe를 이용한 mobility shift assays (EMSA)에서 핵단백질이 결합함을 관찰하였고, 컴퓨터를 이용한 분석에서 TG-interacting factor (TGIF)에 대한 consensus sequences 존재함을 관찰하였다. TGIF 만을 포함하는 probe (TC)와 돌연변이를 유발한 probe (mTG)를 이용한 EMSA에서 이 자리에 TGIF가 결합함을 보였다. 또한, TGIF 자리에 돌연변이를 유발하면(pGL3-mTGIF) 발현의 억제가 회복됨을 관찰하였다. 본 연구에서는 HCCR promoter의 특성을 분석하였고, 이 과정에서 -390에서 -366 사이에 TGIF 전사인자가 결합하여 전사활성을 조절함을 증명하였다.

• Animal cells and systems
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• 제15권3호
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• pp.227-233
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• 2011

The Nramp1/Slc11a1 locus encodes a proton-coupled divalent cation transporter, expressed in late endosomes/lysosomes of macrophages, that constitutes a component of the innate immune response to combat intracellular pathogens and it was shown to play an important role in regulating inherent immunity. The previously identified Z-DNA forming polymorphic repeat(GT)n in the promoter region of the human Nramp1 gene does act as a functional polymorphism influencing gene expression. Research has shown that INF-${\gamma}$, TNF-${\alpha}$, IL-$1{\beta}$ and bacteria LPS increase the level of Nramp1 expression. However, the molecular mechanism for Nramp1 gene regulation is unclear. In this research, bovine Nramp1 5'-flanking region (-1748~+769) was cloned and analyzed by bioinformatics. Then to find the core promoter and the cis-acting elements, deletion analysis of promoter was performed using a set of luciferase reporter gene constructs containing successive deletions of the bovine Nramp1 5'-flanking regions. Promoter activity analysis by the dual luciferase reporter assay system showed that the core promoter of Nramp1 was located at +58~-89 bp. Some positive regulatory elements are located at -89~-205 bp and -278~-1495 bp. And the repressor elements were in region -205~-278 bp, intron1 and -1495~-1748 bp. LPS-responsive regions were located at -1495~-1748 bp and -278~-205 bp. The present study provides an initial effort to explore the molecular mechanism of transcriptional activation of the bovine Nramp1 gene and should facilitate further studies to decode the complex regulatory process and for molecular breeding for disease resistance in bovines.

• Archives of Pharmacal Research
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• 제26권1호
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• pp.58-63
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• 2003

Ginseng has been recommended to alleviate the menopausal symptoms, which indicates that components of ginseng very likely contain estrogenic activity. We have examined the possibility that a component of Panax ginseng, $ginsenoside-R_{b1}$ acts by binding to estrogen receptor. We have investigated the estrogenic activity of $ginsenoside-R_{b1}$ in a transient transfection system using estrogen-responsive luciferase plasmids in MCF-7 cells. $ginsenoside-R_{b1}$ activated the transcription of the estrogen-responsive luciferase reporter gene in MCF-7 breast cancer cells at a concentration of 50 $\mu$M. Activation was inhibited by the specific estrogen receptor antagonist ICI 182,780, indicating that the estrogenic effect of $ginsenoside-R_{b1}$ is estrogen receptor dependent. Next, we evaluated the ability of $ginsenoside-R_{b1}$ to induce the estrogen-responsive gene c-fos by semi-quantitative RT-PCR assays and Western analyses. $ginsenoside-R_{b1}$ increased c-fos both at mRNA and protein levels. However, $ginsenoside-R_{b1}$ failed to activate the glucocorticoid receptor, the retinoic acid receptor, or the androgen receptor in CV-1 cells transiently transfected with the corresponding steroid hormone receptors and hormone responsive reporter plasmids. These data support our hypothesis that $ginsenoside-R_{b1}$ acts a weak phytoestrogen, presumably by binding and activating the estrogen receptor.

• Molecules and Cells
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• 제21권2호
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• pp.261-268
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• 2006

The Drosophila methuselah (mth) mutant has an approximately 35 percent increase in average lifespan, and enhanced resistance to various forms of stress, including starvation, high temperature, and dietary paraquat. To examine the transcriptional regulation of mth, we used luciferase assays employing Drosophila S2 cells. Two positive control elements were found at -542 ~ -272 (PE1) and +28 ~ +217 (PE2), where putative binding sites for transcription factors including Dorsal (Dl) were identified. Cotransfection of a Dl expression plasmid with a mth-luciferase reporter plasmid resulted in decreased reporter activity. PE1 and PE2, the minimal elements for strong promoter activity, were required for maximal repression by Dl protein. The N-terminal Rel homology domain (RHD) of Dl was not sufficient for repression of mth. We demonstrated by chromatin affinity precipitation (ChAP) assays in S2 cells that Dl bound to the putative PE1 binding site. Unexpectedly, semi-quantitative RT-PCR analysis revealed that the level of mth transcripts was reduced in dl flies. However, the in vivo result support the view that mth expression is regulated by dl, since it is well known that Dl functions as both a transcriptional activator and repressor depending on what other transcription factors are present. These findings suggest that both innate immunity and resistance to stress are controlled by Dl protein.

• 한국정보통신학회논문지
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• 제18권2호
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• pp.482-487
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• 2014

본 연구는 testosterone이 지방세포생성에 미치는 영향과 그것에 대한 분자생물학적 조절기전을 역전사-중합효소 연쇄반응과 일시적인 형질전환 분석을 통해 조사하였다. 정소절제수술 마우스(CAST)에 비해 testosterone이 처리된 정소절제수술 마우스(CAST+T)는 백색지방조직 무게와 지방세포 특이유전자($PPAR{\gamma}$와 aP2)의 발현이 감소되었다. In vivo 결과와 일치되게, testosterone 처리는 분화된 3T3-L1세포에서의 triglyceride축적과 지방세포 특이유전자($PPAR{\gamma}$와 aP2)의 발현을 억제시켰다. Testosterone에 의해 활성화된 androgen receptor(AR)는 $PPAR{\gamma}$ transfection에 의해 유도된 luciferase reporter gene 활성을 억제하였다. 따라서 본 연구결과는 testosterone이 AR을 통해 지방세포분화에 대한 $PPAR{\gamma}$의 작용을 억제 조절한다는 것을 시사하고 있다.