• Biomedical Science Letters
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• v.12 no.3
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• pp.131-137
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• 2006

RGS is a negative regulator of G-protein signaling and can be identified by the presence of a conserved $120{sim}125$ amino acid motif, which is referred to as the RGS box. A number of RGSs are induced in response to a wide variety of stimuli. Increased levels of RGSs lead to significant decreases in GPCR responsiveness. To obtain further evidence of a role of RGS proteins in rat C6 astrocytoma cells, we first determined the expression profile of RGS-specific mRNA in C6 cells using reverse transcription-polymerase chain reaction (RT-PCR) with a poly dT18 primer and transcript-specific primers. We found that RGS2, RGS3, RGS6, RGS9, RGS10, RGS12, and RGS16 were differentially expressed in C6 astrocytoma cells. The highest expression rate was found for RGS3, followed by RGS16, RGS10 and RGS9, whereas the expression level for RGS2 was barely detectable. We next assessed whether forskolin regulated the expression of RGSs expressed in C6 astrocytoma cells. The present study found that forskolin dose-dependently stimulated the expression of RGS2 transcripts. This up-regulation of RGS2 gene was abrogated by H-89, potent and broad-spectrum protein kinase A (PKA) inhibitors. Actinomycin D completely inhibited the up-regulation of RGS2 gene induced by forskolin $(10{\mu}M)$, indicating that the regulation of RGS2 gene is controlled at the transcriptional level. In addition, forskolin did significantly activate transcriptional cAMP response element (CRE) in either HEK 293 cells or C6 cells and did not modulate the $NF-{\kappa}B$ and AP-l activity as measured by luciferase reporter gene assay. Finally, forskolin induced the expression of RGS2 mRNA in C6 astrocytoma cells, which depend on the PKA pathway and CRE transcriptional pathways.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2002.10a
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• pp.170-170
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• 2002

College of Pharmacy, Ewha womans University, Seoul, 120-750, Korea 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most potent halogenated aromatic hydrocarbon congener that induces expression of several genes including CYP1A1. Exposure to TCDD results in many toxic actions such as carcinogenesis, hepatotoxicity, immune suppression, and reproductive and developmental toxicity. Dramatic differences in dioxin toxicity have been observed between the sexes of some animal species, suggesting hormonal modulation of dioxin action. Many studies have been reported and propose several mechanisms of anti-estrogenic effects of TCDD. In contrast, the effect of estrogen on the regulation of CYP1A1 are not clear at present. There are several reports showing conflicting results. It seems that induction/inhibition of CYP1A1 may be dependent on cell-type and concentration. The purpose of this study was to investigate the regulation of TCDD-induced CYP1A1 gene expression by estradiol and its metabolites. We examined whether estradiol and its metabolites altered TCDD-mediated induction of CYP1A1 enzyme activity. 17 ${\beta}$ estradiol and 16 ${\alpha}$ estriol at non cytotoxic concentrations caused a significant concentration dependent decline of TCDD-induced EROD activity To determine whether reduced EROD activity reflected altered CYP1A1 mRNA expression, we measured CYP1A1 mRNA level by RT-PCR. And to examine whether estradiol and its metabolites have effects on TCDD-induced CYP1A1 gene expression at the transcription level, we also peformed transient transfection with an AhR responsive reporter plasmid containing the 5' flanking region of the human CYP1A1 gene to examine whether estradiol and its metabolites have effects on TCDD-induced CYP1A1 gene expression at the transcription level.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.5
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• pp.265-272
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• 2010

Follicular cystic ovary (FCO) is one of the most frequently diagnosed ovarian diseases and is a major cause of reproductive failure in mammalian species. However, the mechanism by which FCO is induced remains unclear. Genetic alterations which affect the functioning of many kinds of cells and/or tissues could be present in cystic ovaries. In this study, we performed a comparison analysis of gene expression in order to identify new molecules useful in discrimination of bovine FCO with follicular cystic follicles (FCFs). Normal follicles and FCFs were classified based on their sizes (5 to 10 mm and $\geq25mm$). These follicles had granulosa cell layer and theca interna and the hormone $17{\beta}$-estradiol ($E_2$)/ progesterone ($P_4$) ratio in follicles was greater than one. Perifollicular regions including follicles were used for the preparation of RNA or protein. Differentially expressed genes (DEG) that showed greater than a 2-fold change in expression were screened by the annealing control primer (ACP)-based PCR method using $GeneFishing^{TM}$ DEG kits in bovine normal follicles and FCFs. We identified two DEGs in the FCFs: ribosomal protein L15 (RPL15) and microtubule-associated protein 1B (MAP1B) based on BLAST searches of the NCBI GenBank. Consistent with the ACP analysis, semi-quantitative PCR data and Western blot analyses revealed an up-regulation of RPL15 and a down-regulation of MAP1B in FCFs. These results suggest that RPL15 and MAP1B may be involved in the regulation of pathological processes in bovine FCOs and may help to establish a bovine gene data-base for the discrimination of FCOs from normal ovaries.

• Reproductive and Developmental Biology
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• v.34 no.2
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• pp.103-109
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• 2010

Functional regulation of a specific tissue or organ is controlled by a number of ways, including local cell-cell interaction. Of several forms of cell-cell junctional complexes, gap junctions are caught a great attention due to a formation of direct linkage between neighboring cells. Gap junctions are consisted of connexin (Cx) isoforms. In the present study, we evaluated expressional profiling of Cx isoforms in the rat initial segment (IS) of the male reproductive tract at different postnatal ages. The presence and expression of 13 Cx isoform mRNAs were determined by semi-quantitative real-time PCR analyses. A total of 8 Cx isoform mRNAs were detected in the IS of the male rats during postnatal development. The highest level of Cx30.3 mRNA was found at 5 months of age, while abundance of Cx31 mRNA was the highest at 1 year of age. Expression of Cx31.1 gene was relatively consistent during the postnatal development. Fluctuation of Cx32 and 37 gene expression was observed during the postnatal period. Significant elevation of Cx40 mRNA abundance was detected at 25 days of age and older ages. Expression patterns of Cx43 and 45 genes were similar with the highest level at 2 weeks of age, followed by gradual decreases at older ages. These results indicate differential regulation on expression of Cx isoforms in the rat IS during postnatal development. A complicated regulation of gene expression of Cx isoforms in the IS at different postnatal ages is suggested.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.183-196
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• 2023

Interferon-alpha inducible protein 6 (IFI6) is an interferon-stimulated gene (ISG), belonging to the FAM14 family of proteins and is localized in the mitochondrial membrane, where it plays a role in apoptosis. Transcriptional regulation of this gene is poorly understood in the context of inflammation by intracellular nucleic acid-sensing receptors and pathological conditions caused by viral infection. In this study, chicken IFI6 (chIFI6) was identified and studied for its molecular features and transcriptional regulation in chicken cells and tissues, i.e., lungs, spleens, and tracheas from highly pathogenic avian influenza virus (HPAIV)-infected chickens. The chIFI6-coding sequences contained 1638 nucleotides encoding 107 amino acids in three exons, whereas the duck IFI6-coding sequences contained 495 nucleotides encoding 107 amino acids. IFI6 proteins from chickens, ducks, and quail contain an IF6/IF27-like superfamily domain. Expression of chIFI6 was higher in HPAIV-infected White Leghorn chicken lungs, spleens, and tracheas than in mock-infected controls. TLR3 signals regulate the transcription of chIFI6 in chicken DF-1 cells via the NF-κB and JNK signaling pathways, indicating that multiple signaling pathways differentially contribute to the transcription of chIFI6. Further research is needed to unravel the molecular mechanisms underlying IFI6 transcription, as well as the involvement of chIFI6 in the pathogenesis of HPAIV in chickens.

• The Korean Society of Law and Medicine
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• v.17 no.2
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• pp.85-124
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• 2016

The Human gene testing act (GenDG) in Germany starts from the characteristic features of gene testing, i.e. dualisting structure consisted of anlaysis on the one side and the interpretation on the other side. The linguistic distincion of 'testing', 'anlaysis' and 'judgment' in the act is a fine example. Another important basis of the regulation is the ideological purpose of the law, that is information autonomy. The normative texts as such and the founding principle are the basis of the classification of testing types. Especially in the case of gene testing for medical purpose is classified into testing for diagnostic purpose and predictive purpose. However, those two types are not always clearly differentiated because the predictive value of testing is common in both types. In the legal regulation of gene testing it is therefore important to manage the uncertainty and subjectivity which are inherent in the gene-analysis and the judgment. In GenDG the system ensuring the quality of analysis is set up and GEKO(Commity for gene tisting) based on the section 23 of GenDG concretes the criterium of validity through guidelines. It is also very important in the case of gene testing for medical purpose to set up the system for ensurement of procedural rationality of the interpretation. The interpretation of the results of analysis has a wide spectrum because of the consistent development of technology on the one side and different understandings of different subjects who performs gene testings. Therefore the process should include the communication process for patients in oder that he or she could understand the meaning of gene testing and make plans of life. In GenDG the process of genetic counselling and GEKO concretes the regulation very precisely. The regulation as such in GenDG seems to be very suggestive to Korean legal polic concerning the gene testing.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1485-1491
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• 2008

Tylosin biosynthesis is controlled in cascade fashion by multiple transcriptional regulators, acting positively or negatively, in conjunction with a signalling ligand that acts as a classical inducer. The roles of regulatory gene products have been characterized by a combination of gene expression analysis and fermentation studies, using engineered strains of S. fradiae in which specific genes were inactivated or overexpressed. Among various novel features of the regulatory model, involvement of the signalling ligand is not essential for tylosin biosynthesis.

• Molecular & Cellular Toxicology
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• v.1 no.3
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• pp.203-208
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• 2005

Thioacetamide (TA) is potent haptotoxincant that requires metabolic activation by mixed-function oxidases. Micrcarray technology, which is massive parallel gene expression profiling in a single hybridization experiment, has provided as a powerful molecular genetic tool for biological system related toxicant. In this study we focus on the use of toxicogenomics for the determination of gene expression analysis associated with hepatotoxicity in rat liver epithelial cell line WB-F344 (WB). The WB cells was used to assess the toxic effects of TA. WB cells were exposed to two concentrations of TA-doses which caused 20% and 50% cell death were chosen and the cells exposed for periods of 2 and 24 h. Our data revealed that following the 2-h exposure at the both of doses and 24-h exposure at the low doses, few changes in gene expression were detected. However, after 24-h exposure of the cells to the high concentration, multiple changes in gene expression were observed. TA treatment gave rise predominantly to up-regulation of genes involved in cell cycle and cell death, but down-regulation of genes involves in cell adhesion and calcium ion binding. Exposure of WB cells to higher doses of the TA gave rise to more changes in gene expression at lower exposure times. These results show that TA regulates expression of numerous genes via direct molecular signaling mechanisms in liver cells.

• BMB Reports
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• v.36 no.3
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• pp.326-331
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• 2003

The fission yeast cells that contained the cloned glutathione synthetase (GS) gene showed 1.4-fold higher glutathione (GSB) content and 1.9-fold higher GS activity than the cells without the cloned GS gene. Interestingly, $\gamma$-glutamylcysteine synthetase activity increased 2.1-fold in the S. pombe cells that contained the cloned GS gene. The S. pombe cells that harbored the multi copy-number plasmid pRGS49 (containing the cloned GS gene) showed a higher level of survival on solid media with cadmium chloride (1 mM) or mercuric chloride ($10\;{\mu}M$) than the cells that harbored the YEp357R vector. The 506 bp upstream sequence from the translational initiation point and N-terminal8 amino acid-coding region were fused into the promoteriess $\beta$-galactosidase gene of the shuttle vector YEp367R to generate the fusion plasmid pUGS39. Synthesis of $\beta$-galactosidase from the fusion plasmid pUGS39 was significantly enhanced by cadmium chloride and NO-generating S-nitroso-N-acetylpenicillamine (SNAP) and sodium nitroprusside (SN). It was also induced by L-buthionine-(S,R)-sulfoximine, a specific inhibitor of $\gamma$-glutamylcysteine synthetase (GCS). We also found that the expression of the S. pombe GS gene is regulated by the Atf1-Spc1-Wis1 signal pathway.

• Molecules and Cells
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• v.26 no.3
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• pp.285-290
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• 2008

Estrogen-induced proliferation in estrogen receptor (ER)-positive breast cancer cells is primarily mediated through two distinct intracellular receptors, $ER{\alpha}$ and $ER{\beta}$. Although tumor necrosis factor alpha ($TNF{\alpha}$) and $E2/ER{\alpha}$ are known to exert opposing effects on cell proliferation in MCF-7 cells, the mechanism by which $TNF{\alpha}$ antagonizes $E2/ER{\alpha}$-mediated cell proliferation is not well understood. The present study suggests that reduced cell survival in response to $TNF{\alpha}$ treatment in MCF-7 cells may be associated with the down-regulation of $ER{\alpha}$ protein. The decrease in $ER{\alpha}$ protein level was accompanied by an inhibition of $ER{\alpha}$ gene transcription. Cell viability was decreased synergistically by the combined treatment with $ER{\alpha}$-siRNA and $TNF{\alpha}$. Furthermore, pretreatment of cells with the PI3-kinase (PI3K)/ Akt inhibitor, LY294002, markedly enhanced $TNF{\alpha}$-induced down-regulation of the $ER{\alpha}$ protein, suggesting that the PI3K/Akt pathway might be involved in control of the $ER{\alpha}$ level. Moreover, down-regulation of $ER{\alpha}$ by $TNF{\alpha}$ was not inhibited in cells that were pretreated with the proteasome inhibitors, MG132 and MG152, which suggests that proteasome-dependent proteolysis does not significantly influence $TNF{\alpha}$-induced down-regulation of $ER{\alpha}$ protein. In contrast, the effect of the PI3K/Akt inhibitor on $ER{\alpha}$ was blocked in cells that were treated with LY294002 in the presence of the proteasome inhibitors. Collectively, our findings show that the $TNF{\alpha}$ may partly regulate the growth of MCF-7 breast cancer cells through the down-regulation of $ER{\alpha}$ expression, which is primarily mediated by a PI3K/Akt signaling.