• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.74-79
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• 2002

In addition to the well-established use of positron emission tomography (PET) in clinical oncology, novel roles for PET are rapidly emerging in the field of gene therapy. Methods for controlled gene delivery to living bodies, made available through advances in molecular biology, are currently being employed in animals for research purposes and in humans to treat diseases such as cancer. Although gene therapy is still in its early developmental stage, it is perceived that many serious illnesses could be treated successfully by the use of therapeutic gene delivery. A major challenge for the widespread use of human gene therapy is to achieve a controlled and effective delivery of foreign genes to target cells and subsequently, adequate levels of expression. As such, the availability of noninvasive imaging methods to accurately assess the location, duration, and level of transgene expression is critical for optimizing gene therapy strategies. Current endeavors to achieve this goal include methods that utilize magnetic resonance imaging, optical imaging, and nuclear imaging techniques. As for PET, reporter systems that utilize genes encoding enzymes that accumulate positron labeled substrates and those transcribing surface receptors that bind specific positron labeled ligands have been successfully developed. More recent advances in this area include improved reporter gene constructs and radiotracers, introduction of potential strategies to monitor endogenous gene expression, and human pilot studies evaluating the distribution and safety of reporter PET tracers. The remarkably rapid progress occurring in gene imaging technology indicates its importance and wide range of application. As such, gene imaging is likely to become a major and exciting new area for future application of PET technology.

• Journal of Life Science
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• v.14 no.5
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• pp.732-740
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• 2004

MCM proteins are essential for eukaryotic DNA replication, playing roles in the initiation and elongation of DNA replication. MCM proteins expression is much higher in malignant tissues than normal tissues. Several reports have indicated the usefulness of MCM proteins as markers of cancer cells in histopathological diagnosis. However, the cause of enhanced expression of MCM proteins in cancer cells remain to be clarified. The purpose of this study is to examine the relative transcriptional activities of human mcm gene promoters in cancer and normal cells. The minimal promoter region required for transcription of a luciferase reporter gene was contained an E-box and one E2F site. In addition, luciferase activities from mcm7 and mcm2 promoter/luciferase gene reporter constructs were significantly increased in cancer cells at 8 times compared with normal cells. E-box and E2F binding site in the promoter of mcm genes are responsible for different mechanism of transcription regulation on the cellular environment.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.620-624
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• 2016

The Wnt/β-catenin signaling pathway is mandatory in adipogenesis. In this study, we investigated the applicability of functional materials for the treatment of obesity by examining Wnt/β-catenin pathway reporter activity related to adipocyte differentiation inhibiting with korean native plant extracts. The luciferase activity of HEK 293-TOP cells increased the reporter activity approximately 152% and 130% by treatment with Sanguisorba officinalis and Thuja orientalis, respectively. Ricinus communis were represented about 90% higher activity, two samples(Rosa rugosa and Sophorae Flos) showed 80% higher activity than the control. Three samples of plant extracts (Zanthoxylum piperitum, Pueraria thunbergiana, Solanum nigrum) were about 70% higher activity compared with the non-treated control. Cytotoxicity of plant extracts was not detected in the rat neural stem cells. These results suggest that the selected eight plant extracts are safe compounds. Our findings indicate that Wnt/β-catenin pathway reporter activity could be used for high throughput screening system. In addition, the plant extracts selected as candidates for adipocyte differentiation inhibiting may be potential therapeutic agents for obesity, it will be exploring the possibility of developing an anti-obesity materials through further experiments with selected plant extracts.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.109-109
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• 2017

The core components of ABA-dependent gene expression signaling have been identified in Arabidopsis and rice. This signaling pathway consists of four major components; group A OsbZIPs, SAPKs, subclass A OsPP2Cs and OsPYL/RCARs in rice. These might be able to make thousands of combinations through interaction networks resulting in diverse signaling responses. We tried to characterize those gene functions using transient gene expression for rice protoplasts (TGERP) because it is instantaneous and convenient system. Firstly, in order to monitor the ABA signaling output, we developed reporter system named pRab16A-fLUC which consists of Rab16A promoter of rice and luciferase gene. It responses more rapidly and sensitively to ABA than pABRC3-fLUC that consists of ABRC3 of HVA1 promoter in TGERP. We screened the reporter responses for over-expression of each signaling components from group A OsbZIPs to OsPYL/RCARs with or without ABA in TGERP. OsbZIP46 induced reporter most strongly among OsbZIPs tested in the presence of ABA. SAPKs could activate the OsbZIP46 even in the ABA independence. Subclass A OsPP2C6 and -8 almost completely inhibited the OsbZIP46 activity in the different degree through the SAPK9. Lastly, OsPYL/RCAR2 and -5 rescued the OsbZIP46 activity in the presence of SAPK9 and OsPP2C6 dependent on ABA concentration and expression level. By using TGERP, we could characterize successfully the effects of ABA dependent gene expression signaling components in rice. In conclusion, TGERP represents very useful technology to study systemic functional genomics in rice or other monocots.

• BMB Reports
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• v.36 no.6
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• pp.586-592
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• 2003

Four putative promoters of the temperate mycobacteriophage L1 were cloned by detecting the $\beta$-galactosidase reporter expression in E. coli transformants that carried L1 specific operon-fusion library. All of the four L1 promoters were also found to express differentially in the homologous environment of mycobacteria. Of the four promoters, two were suggested to be the putative early promoters of L1 since they express within 0 to 10 min of the initiation of the lytic growth of L1. One of the putative early promoters showed a relatively better and almost identical activity in both E. coli and M. smegmatis. By a sequence analysis, we suggest that the L1 insert that contained the stronger early promoter possibly carries two convergent E. coli $\sigma^{70}$-like L1 promoters, which are separated from each other by about 300 nucleotides. One of them is the early promoter of L1 as it showed a 100% similarity with the early $P_{left}$ promoter of the homoimmune phage L5. The second promoter, designated P4, was suggested for its appreciable level of reporter activity in the absence of the -10 element of the $P_{left}$ equivalent of L1. By analyzing most of the best characterized mycobacteriophages-specific promoters, including the L1 promoter P4, we suggest that both the -10 and -35 hexamers of the mycobacteriophage promoters are highly conserved and almost similar to the consensus -10 and -35 hexamers of the E. coli $\sigma^{70}$ promoters.

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.83-85
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• 2007

Deep-sea bacteria are adapted to extreme environments, such as high pressures and cold temperatures. We have isolated many piezophiles which grow well even under high pressures from deep-sea sediment. Shewanella violacea DSS12 and Moritella japonica DSK1 have the ability to grow at up to 70 MPa, and those bacteria have unique mechanisms of gene expression in response to high pressure conditions. The combination of gene expression systems in piezophiles, like the high pressure-dependent promoters and GFP reporter gene, may reveal highly fluorescent cells when exposed to high hydrostatic pressure conditions. It is predicted that a novel bio-sensing system can be made to probe high pressure environments using living bacteria. First, gene transformation into our piezophiles, strains DSS12 and DSK1, were examined. Eschericha coli S17-1 was used for bacterial conjugation with those piezophiles. As a result, the broad host range vector, pKT231, and the shuttle vector, pTH10, were successfully introduced to DSS12 and DSK1, respectively. Next, The pressure regulated promoters from DSS12 and DSK1 were cloned into proper vectors and combined with GFP as a reporter gene downstream of each promoter. The transformants of DSK1 and DSS12 with the recombinant pTH10 and pKT231 plasmid, which has cadA and glnA promoters (each of them is a pressure regulated promoter from DSK1 and DSS12, respectively) and GFP, were grown under high pressure and gene expression of GFP promoted by 50 MPa pressure was confirmed. This is a critical point to create a pressure-sensing bacteria, as the "High Pressure Glow Cells", which will indicate the level of environmental pressure using fluorescence of GFP as a reporter gene.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.179-179
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• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1A1. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.

• IMMUNE NETWORK
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• v.11 no.1
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• pp.1-10
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• 2011

Interleukin-7 (IL-7) is an essential cytokine for T cells. However, IL-7 is not produced by T cells themselves such that T cells are dependent on extrinsic IL-7. In fact, in the absence of IL-7, T cell development in the thymus as well as survival of naive T cells in the periphery is severely impaired. Furthermore, modulating IL-7 availability in vivo either by genetic means or other experimental approaches determines the size, composition and function of the T cell pool. Consequently, understanding IL-7 expression is critical for understanding T cell immunity. Until most recently, however, the spatiotemporal expression of in vivo IL-7 has remained obscured. Shortage of such information was partly due to scarce expression of IL-7 itself but mainly due to the lack of adequate reagents to monitor IL-7 expression in vivo. This situation dramatically changed with a recent rush of four independent studies that describe the generation and characterization of IL-7 reporter mice, all utilizing bacterial artificial chromosome transgene technology. The emerging consensus of these studies confirmed thymic stromal cells as the major producers of IL-7 but also identified IL-7 reporter activities in various peripheral tissues including skin, intestine and lymph nodes. Strikingly, developmental and environmental cues actively modulated IL-7 reporter activities in vivo suggesting that IL-7 regulation might be a new mechanism of shaping T cell development and homeostasis. Collectively, the availability of these new tools opens up new venues to assess unanswered questions in IL-7 biology in T cells and beyond.

• Journal of Ginseng Research
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• v.44 no.5
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• pp.690-696
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• 2020

Background: As the main metabolites of ginsenosides, 20(S, R)-protopanaxadiol [PPD(S, R)] and 20(S, R)-protopanaxatriol [PPT(S, R)] are the structural basis response to a series of pharmacological effects of their parent components. Although the estrogenicity of several ginsenosides has been confirmed, however, the underlying mechanisms of their estrogenic effects are still largely unclear. In this work, PPD(S, R) and PPT(S, R) were assessed for their ability to bind and activate human estrogen receptor α (hERα) by a combination of in vitro and in silico analysis. Methods: The recombinant hERα ligand-binding domain (hERα-LBD) was expressed in E. coli strain. The direct binding interactions of ginsenosides with hERα-LBD and their ERα agonistic potency were investigated by fluorescence polarization and reporter gene assays, respectively. Then, molecular dynamics simulations were carried out to simulate the binding modes between ginsenosides and hERα-LBD to reveal the structural basis for their agonist activities toward receptor. Results: Fluorescence polarization assay revealed that PPD(S, R) and PPT(S, R) could bind to hERα-LBD with moderate affinities. In the dual luciferase reporter assay using transiently transfected MCF-7 cells, PPD(S, R) and PPT(S, R) acted as agonists of hERα. Molecular docking results showed that these ginsenosides adopted an agonist conformation in the flexible hydrophobic ligand-binding pocket. The stereostructure of C-20 hydroxyl group and the presence of C-6 hydroxyl group exerted significant influence on the hydrogen bond network and steric hindrance, respectively. Conclusion: This work may provide insight into the chemical and pharmacological screening of novel therapeutic agents from ginsenosides.

• The Journal of Natural Sciences
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• v.11 no.1
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• pp.89-94
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• 1999

ALG-2 (apoptosis linked gene-2) is a 22 kDa calcium-binding protein necessary for apoptosis induced by various stimuli in lymphocyte. The transactivation of human ALG-2 was assessed in yeast as a fusion protein with the DNA binding domains (DBDs) of LexA. The C-terminal of hALG-2 (93-191 amino acid) exhibited transacitivation of the reporter gene, LacZ, whereas the full-length hALG-2 (1-91 amino acid) and its N-terminal (1-98 amino acid) did not. The transactivation of LacZ reporter was driven more strongly (more than 2.7-fold increase) by the C-terminus of hALG-2 than by the B42, as a positive control for transactivation. Hence, our data suggested a possible regulatory role of the N-termini of hALG-2 upon transactivation.