• Journal of Life Science
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• v.5 no.4
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• pp.162-169
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• 1995

The glpD genes encoding gly-3-p dehydrogenase is essential for the aerobic growth of E. coli on glycerol or gly-3-p. The glpE gene, the function of which is unknownm is transcribed divergently with respect to glpD gene. Expression of the adjacent but divergently transcribed glpD the glpE genes is positively regulated by the cAMP-CRP complex. In this study, for a precise investigation of the functional elements in the regulatory region for transcription activation by cAMP-CRP, deletion mutation have been introducted into the regulatory region. The effect of the deletion mutant on transcriptional regulation was tested in vivo by $\beta$-galctosidase activity. Deletion mutants in the regulatory region of glpD demonstrated that the presence of the CRP-binding site resulted in an sixfold increase in promoter activity. And also deletion mutants of glpE gene demonstrated that the presence of the CRP-binding site resulted in an eightfold increase in promoter activity. Insertion of 22 bp oligomer in the deletion mutants has shown that the CRP binding site is need for maximal expression of glpD and glpE genes. glpD and glpE gene, cAMP-CRP complex, deletion mutant, transcriptional regulation.

• Molecules and Cells
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• v.19 no.2
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• pp.279-282
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• 2005

In mammals, 7-dehydrocholesterol reductase (Dhcr7) is the terminal enzyme in cholesterol biosynthesis. We previously reported that the Dhcr7 proximal promoter (-179 to +1), which contains CpG islands, is responsible for sterol-mediated expression of the rat gene. In the present study, we examined whether methylation of this region affects the transcriptional activity of the Dhcr7 gene. In vitro DNA methylation of the Dhcr7 promoter and luciferase-reporter assays showed that DNA methylation of the CpG islands suppressed transcription. Furthermore, treatment of the methylated Dhcr7 promoter with the demethylating agent, 5-aza-2'-deoxycytidine (5-Aza-CdR), reversed the suppression of promoter activity. These results indicate that methylation of the CpG islands is an important transcriptional regulatory mechanism in the Dhcr7 promoter.

• BMB Reports
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• v.42 no.7
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• pp.411-417
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• 2009

Transcriptional activation domain (TAD) in virion protein 16 (VP16) of herpes simplex virus does not have any globular structure, yet exhibits a potent transcriptional activity. In order to probe the structural basis for the transcriptional activity of VP16 TAD, we have used NMR spectroscopy to investigate its detailed structural features. Results show that an unbound VP16 TAD is not merely "unstructured" but contains four short motifs (residues 424-433, 442-446, 465-467 and 472-479) with transient structural order. Pre-structured motifs in other intrinsically unfolded proteins (IUPs) were shown to be critically involved in target protein binding. The 472-479 motif was previously shown to bind to $hTAF_{II}31$, whereas the $hTAF_{II}31$-binding ability of other motifs found in this study has not been addressed. The VP16 TAD represents another IUP whose pre-structured motifs mediate promiscuous binding to various target proteins.

• BMB Reports
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• v.56 no.9
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• pp.508-513
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• 2023

The phytochemical quercetin has gained attention for its anti-inflammatory and anti-tumorigenic properties in various types of cancer. Tumorigenesis involves the aberrant regulation of kinase/phosphatase, highlighting the importance of maintaining homeostasis. Dual Specificity Phosphatase (DUSP) plays a crucial role in controlling the phosphorylation of ERK. The current study aimed to clone the DUSP5 promoter, and investigate its transcriptional activity in the presence of quercetin. The results revealed that quercetin-induced DUSP5 expression is associated with the serum response factor (SRF) binding site located in the DUSP5 promoter. The deletion of this site abolished the luciferase activity induced by quercetin, indicating its vital role in quercetin-induced DUSP5 expression. SRF protein is a transcription factor that potentially contributes to quercetin-induced DUSP5 expression at the transcriptional level. Additionally, quercetin enhanced SRF binding activity without changing its expression. These findings provide evidence of how quercetin affects anti-cancer activity in colorectal tumorigenesis by inducing SRF transcription factor activity, thereby increasing DUSP5 expression at the transcriptional level. This study highlights the importance of investigating the molecular mechanisms underlying the anti-cancer properties of quercetin, and suggests its potential use in cancer therapy.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.421-427
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• 2012

The production of therapeutic proteins from transgenic animals is one of the most important successes of animal biotechnology. Milk is presently the most mature system for production of therapeutic proteins from a transgenic animal. Specifically, ${\beta}$-casein is a major component of cow, goat and sheep milk, and its promoter has been used to regulate the expression of transgenic genes in the mammary gland of transgenic animals. Here, we cloned the porcine ${\beta}$-casein gene and analyzed the transcriptional activity of the promoter and intron 1 region of the porcine ${\beta}$-casein gene. Sequence inspection of the 5'-flanking region revealed potential DNA elements including SRY, CdxA, AML-a, GATA-3, GATA-1 and C/EBP ${\beta}$. In addition, the first intron of the porcine ${\beta}$-casein gene contained the transcriptional enhancers Oct-1, SRY, YY1, C/EBP ${\beta}$, and AP-1, as well as the retroviral TATA box. We estimated the transcriptional activity for the 5'-proximal region with or without intron 1 of the porcine ${\beta}$-casein gene in HC11 cells stimulated with lactogenic hormones. High transcriptional activity was obtained for the 5'-proximal region with intron 1 of the porcine ${\beta}$-casein gene. The ${\beta}$-casein gene containing the mutant TATA box (CATAAAA) was also cloned from another individual pig. Promoter activity of the luciferase vector containing the mutant TATA box was weaker than the same vector containing the normal TATA box. Taken together, these findings suggest that the transcription of porcine ${\beta}$-casein gene is regulated by lactogenic hormone via intron 1 and promoter containing a mutant TATA box (CATAAAA) has poor porcine ${\beta}$-casein gene activity.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.516-521
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• 2014

The mechanisms underlying the refractory effects of flutamide, a first-line oral anti-androgen drug, have not been entirely elucidated. In the present study, we investigated the mechanism of flutamide-induced hormone-refractory prostate cancer cell growth and its modulation by resveratrol, a phytoalexin present in grapes. Resveratrol significantly attenuated interleukin 6 (IL-6)-induced signal transducer and activator of transcription 3 (STAT3) transcriptional activity and dihydrotestosterone (DHT) or IL-6-induced prostate-specific antigen (PSA) transcriptional activity. Furthermore, compared to treatment with DHT or IL-6 alone, combination treatment of cells significantly increased PSA transcriptional activity, and resveratrol markedly diminished DHT plus IL-6-induced STAT3 and PSA transcriptional activities. Thus, the inhibitory effects of resveratrol on IL-6-, DHT-, and flutamide-induced hormone-refractory prostate cancer cell growth are partly mediated by the suppression of STAT3 reporter gene activity, suggesting that resveratrol represents a promising therapy for prostate cancer.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.495-499
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• 2005

Purpose : Interleukin-4(IL-4) is a critical component of the Th2 cytokine pathway and contributes to severity of respiratory syncytial virus(RSV) bronchiolitis. Previous studies observed an association between severe RSV bronchiolitis in Korean children with a common haplotype of the IL4 promoter. This study was performed to investigate functional differences of the variant IL4 promoter haplotypes. Methods : Genomic DNA was obtained from 20 children from 6 to 48 months of age in the Department of Pediatrics, Seoul National University Bundang Hospital. The IL4 promoter spanning an 1.2 kb region was amplified and haplotype was determined by cloning and the PHASE reconstruction. Transcriptional activity of Jurkat T cells which were transfected with each IL4 haplotype were analyzed by use of luciferase assay. Results : Three haplotypes of the IL4 promoter have been identified with the frequency of GCC(7 percent), TCC(17 percent), and TTT(76 percent). The TTT haplotype demonstrated the highest luciferase values in both unstimulated and PMA-stimulated Jurkat T cells. Increases in transcriptional activity compared to GCC have been shown in TTT(5.3 fold higher) followed by TCC(4.2 fold higher) in unstimulated Jurkat T cells. Conclusion : We provided evidence that increased transcriptional activity of the TTT haplotype of the IL4 promoter, which has previously been over-represented in Korean children with severe RSV bronchiolitis. Therefore, IL-4 could play a potential role in the pathogenesis of RSV infection, possibly via an altered transcriptional activity of the different IL4 haplotypes.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.381-388
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• 2011

Dietary conjugated linoleic acid (CLA) play key roles in lipid metabolism. Here, we investigated the effect of CLA on the transcriptional activity of TR4, an orphan nuclear receptor that plays an important role in lipid homeostasis. CLA increased TR4 gene mRNA level in 3T3-L1 adipocytes, but inhibited TR4 transcriptional activity in a dose-dependent manner. TR4 induced perilipin expression in 3T3-L1 adipocytes by activating perilipin promoter activity. In a gel shift assay, TR4 bound direct to the putative TR4 response element in the perilipin promoter. Interestingly, CLA reduced the interaction between TR4 and consensus DR1, a well-known TR4 binding site. Additionally, CLA inhibited TR4-induced perilipin promoter activity in a dose-dependent manner. Together, our results suggest that CLA may play a role in lipid homeostasis in adipocytes by functionally regulating TR4.

• Development and Reproduction
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• v.16 no.4
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• pp.379-384
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• 2012

Lhx8 (LIM homeobox 8) gene encodes a LIM homeodomain transcriptional regulator that is preferentially expressed in germ cells and critical for mammalian folliculogenesis. However, Lhx8 DNA binding sequences are not characterized yet. We aimed to identify and characterize a cis-acting sequence of germ-cell specific transcriptional factor, Lhx8. To identify Lhx8 DNA binding element, Cyclic Amplification of Sequence Target (CAST) Analysis was performed. Electrophoretic Mobility Shift Assay (EMSA) was processed for the binding specificity of Lhx8. Luciferase assay was for the transcriptional activity of Lhx8 through identified DNA binding site. We identified a putative cis-acting sequence, TGATTG as Lhx8 DNA binding element (LBE). In addition, Lhx8 binds to the LBE with high affinity and augments transcriptional activity of luciferase reporter driven by artificial promoter containing the Lhx8 binding element. These findings indicate that Lhx8 directly regulates the transcription of genes containing Lhx8 binding element in oocytes during early folliculogenesis.

• Toxicological Research
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• v.22 no.1
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• pp.15-22
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• 2006

Many of endocrine disrupting chemicals induce effects via interaction with hormone receptors and responsive elements in target cells. We investigated endocrine disrupting effects of some food additives and contaminants including BHA, BHT, ethoxyquin, propionic acid, sorbic acid, benzoic acid, CPM, aflatoxin B1, cadmium chloride, genistein, TCDD and PCBs in yeast transformants expressing human steroid hormone receptors along with steroid responsive elements. The response limit of genetically recombinant yeast to $17{\beta}$-estradiol, testosterone and progesterone was $1{\times}10^{-16},\;1{\times}10^{-12}\;and\;1{\times}10^{-13}M$, respectively. BHT induced weak transcriptional activity in estrogen sensitive yeast, while BHA and sorbic acid interacted weakly with androgen receptor/responsive element. CPM induced transcriptional activities in all types of yeasts sensitive to steroid hormones. Zearalenone and genistein induced high transcriptional activation in estrogen sensitive yeast with relative potencies almost $10^8$ folds lower than $17{\beta}$-estradiol. TCDD induced transcriptional activation weakly in estrogen- and progesterone- sensitive yeasts. This study elucidated that recombinant yeast is a sensitive and high-throughput system and can be used for the direct assessment on chemical interactions with steroid receptors and responsive elements. Also, the present study raises the requirement of evaluation on the endocrine disrupting effects of BHT, BHA, sorbic acid, CPM and TCDD for their transcription activity in yeast screening system though weak in intensity.