• Parasites, Hosts and Diseases
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• v.53 no.4
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• pp.385-394
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• 2015

Leishmaniasis is a worldwide uncontrolled parasitic disease due to the lack of effective drug and vaccine. To speed up effective drug development, we need powerful methods to rapidly assess drug effectiveness against the intracellular form of Leishmania in high throughput assays. Reporter gene technology has proven to be an excellent tool for drug screening in vitro. The effects of reporter proteins on parasite infectivity should be identified both in vitro and in vivo. In this research, we initially compared the infectivity rate of recombinant Leishmania major expressing stably enhanced green fluorescent protein (EGFP) alone or EGFP-luciferase (EGFP-LUC) with the wild-type strain. Next, we evaluated the sensitivity of these parasites to amphotericin B (AmB) as a standard drug in 2 parasitic phases, promastigote and amastigote. This comparison was made by MTT and nitric oxide (NO) assay and by quantifying the specific signals derived from reporter genes like EGFP intensity and luciferase activity. To study the amastigote form, both B10R and THP-1 macrophage cell lines were infected in the stationary phase and were exposed to AmB at different time points. Our results clearly revealed that the 3 parasite lines had similar in vitro infectivity rates with comparable parasite-induced levels of NO following interferon-${\gamma}$/lipopolysaccharide induction. Based on our results we proposed the more reporter gene, the faster and more sensitive evaluation of the drug efficiency.

• Molecules and Cells
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• v.42 no.11
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• pp.783-793
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• 2019

When endoplasmic reticulum (ER) functions are perturbed, the ER induces several signaling pathways called unfolded protein response to reestablish ER homeostasis through three ER transmembrane proteins: inositol-requiring enzyme 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF6). Although it is important to measure the activity of ATF6 that can indicate the status of the ER, no specific cell-based reporter assay is currently available. Here, we report a new cell-based method for monitoring ER stress based on the cleavage of $ATF6{\alpha}$ by sequential actions of proteases at the Golgi apparatus during ER stress. A new expressing vector was constructed by using fusion gene of GAL4 DNA binding domain (GAL4DBD) and activation domain derived from herpes simplex virus VP16 protein (VP16AD) followed by a human $ATF6{\alpha}$ N-terminal deletion variant. During ER stress, the GAL4DBD-VP16AD(GV)-$hATF6{\alpha}$ deletion variant was cleaved to liberate active transcription activator encompassing GV-$hATF6{\alpha}$ fragment which could translocate into the nucleus. The translocated GV-$hATF6{\alpha}$ fragment strongly induced the expression of firefly luciferase in HeLa Luciferase Reporter cell line containing a stably integrated 5X GAL4 site-luciferase gene. The established double stable reporter cell line HLR-GV-$hATF6{\alpha}$(333) represents an innovative tool to investigate regulated intramembrane proteolysis of $ATF6{\alpha}$. It can substitute active pATF6(N) binding motif-based reporter cell lines.

• International Journal of Industrial Entomology and Biomaterials
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• v.24 no.2
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• pp.49-55
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• 2012

We previously isolated 9 clones that show stronger signal compared to B. mori cytoplasmic actin gene (BmA3) by using a dot blot hybridization. In this study, we focused on one clone among these clones which has high amino acid homology with elongation factor ${\alpha}$ gene of B. mori. This clone, named $bEF1{\alpha}$ (B. mori elongation factor ${\alpha}$) was ubiquitously expressed in all tissues and developmental stage of B. mori. As result of promoter assay using dual luciferase assay system, we found the highest transcription activity region (-702/+38) in the 5'-flanking region of $bEF1{\alpha}$ gene, which has about 20 fold more intensive promoter activity than BmA3 promoter. Moreover, the $bEF1{\alpha}$ promoter was normally regulated in Bm5, Sf9, and S2 cells. Therefore, we suggest that $bEF1{\alpha}$ promoter may be used more powerful and effectively for transgene expression in various insects containing B. mori as a universal promoter.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.6
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• pp.636-642
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• 2007

Background: CpG DNA plays an important role in immune cell function. This study examined whether the temporal control of toll-like receptor (TLR)9 by CpG DNA can regulate the expression of matrix metalloproteinase-9(MMP-9). Methods and materials: Macrophages were cultured in the presence of 10% FBS. For the various MMP genes analysis, RT-PCR and real-time PCR were performed. In addition, zymography assay performed for the MMP activity. The phosphorylation assay did for the ERK1/2 and NF${\kappa}B$ activation, and luciferase promoter assay was for the NF${\kappa}B$ activity. Results: CpG DNA induced the mRNA expression of MMP-2, MMP-9, and MMP-13, but not of MMP-7, MMP-8, and MMP-12, in a time-dependent manner. Especially, the mRNA expression of MMP-9 was strongly induced by CpG DNA using real-time RT-PCR. The TLR9 inhibitor, chloroquine, suppressed CpG DNA-induced MMP-9 expression and its activity. Moreover, CpG DNA induced the phosphorylation of ERK and the inhibition of ERK by U0126 suppressed CpG DNA-induced MMP-9 expression and its activity. CpG DNA stimulated $I{\kappa}B-{\alpha}$ degradation and luciferase activity. In addition, pretreatment of SN-50, the inhibitor of NF${\kappa}B$, strongly blocked the CpG DNA-induced MMP-9 expression and activity. Conclusion: These observations suggest that CpG DNA may play important roles in the activation of macrophages by regulating the production of MMP-9 via the sequential TLR9-ERK-NF${\kappa}B$ signaling pathway.

• Journal of Life Science
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• v.19 no.9
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• pp.1289-1293
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• 2009

Proto-oncogene human cervical cancer oncogene (HCCR) functions as a negative regulator of p53 and contributes to tumorigenesis in various human tissues. However, it is unknown how HCCR contributes to the cellular and biochemical mechanisms of human tumorigenesis. In this study, we showed how the expression of HCCR is modulated. The luciferase activity assay indicated that the HCCR 5'-flanking region at positions -370 to -406 plays an important role in the promoter activity. Computational analysis of this region identified one consensus sequence for the TG-interacting factor (TGIF) located at -390 to -366 (TG). Mobility shift assays (EMSA) revealed that nuclear proteins from K562 bind to the TG site, but not to the mutated TG site. The reporter activity assay with promoter constructs carrying mutated TGIF sequences pGL3-mTGIF significantly increased reporter activities compared to wild type constructs pGL3-$406{\sim}+30$. In this study, we characterized the HCCR promoter and found that HCCR expression was partially regulated by the transcription repressor TGIF, which bound the promoter at positions -390 to -366.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.2
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• pp.107-114
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• 2010

For stable germline transformation, the promoter of Bombyx mori cytoplasmic actin gene (BmA3) has been used for ubiquitous expression of transgenes. So far, no strong promoter is available for ubiquitous expression in B. mori, excluding BmA3 promoter. To identify more powerful promoter than previously reported BmA3 promoter, we isolated 9 clones that show stronger signal compared to BmA3 by a dot blot hybridization. Among these 9 clones, we focused on one clone which has high amino acid homology (85%) with hypothetical protein 32 gene of Lonomia obliqua. This clone, named bHp32 (B. mori hypothetical protein 32) was ubiquitously expressed in all tissues and developmental stage of fifth instar B. mori larvae. As result of promoter assay using dual luciferase assay system, we found the highest transcription activity region (-1,200/+220) in the 5'-flanking region of bHp32 gene, which has 42-fold more intensive promoter activity than BmA3 promoter. Moreover, the bHp32 promoter was normally regulated in Bm5, Sf9, and S2 cells. Therefore, we suggest that bHp32 promoter may be used more powerful and effectively for transgene expression in various insects containing B. mori as a universal promoter.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.740-746
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• 2004

In order to identify the anti-inflammatory and analgesic properties of natural herbal extracts, widely used in the Korean traditional medicine, an in vitro screening system was designed using pGL3, a luciferase reporter vector, and the tumor necrosis factor (TNF)-α and cyclooxygenase (COX)-II as target genes. The promoter regions of each gene was generated by PCR using the human chromosome as template DNA, and inserted into pGL3 vector with Kpnl and Hindlll. The final construct was transfected into human myleomonocytic leukemia cells (U937) that could be differentiated and activated by phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). Using this system, we tested the anti-inflammatory and analgesic effects of several herbal extracts being regarded to have the medicinal effects of diminishing the body heat and complementing Qi. The well-known chemicals of PD98059 and berberine chloride were used as controls of the transcriptional inhibitors of TNF-α and COX-II, respectively. Among them, Salvia miltiorrhiza (Dan-Sam) was found to exhibit the significant medicinal properties of anti-inflammatory and analgesic effects.

• 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.

• Journal of Life Science
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• v.28 no.7
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• pp.765-771
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• 2018

Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a key transcription factor that regulates adipogenesis, and epigenetic control of $PPAR{\gamma}$ is of great interest in obesity-inhibition research. Our previous study showed that CACUL1 (CDK2-associated cullin domain 1) acts as a corepressor that inhibits $PPAR{\gamma}$ transcriptional activity and adipocyte differentiation. Here, we investigated the roles of protein arginine methyltransferase 5 (PRMT5), a novel binding partner of CACUL1, in regulating $PPAR{\gamma}$. The interaction between PRMT5 and CACUL1 was shown by immunoprecipitation assay in vivo and GST pulldown assay in vitro. As shown by luciferase reporter assay, PRMT5 and CACUL1 cooperated to inhibit the transcriptional activity of $PPAR{\gamma}$. The suppressive role of PRMT5 in adipogenesis was examined by Oil Red O staining using 3T3-L1 cells, which stably overexpress or deplete PRMT5. Overexpression of PRMT5 suppresses $PPAR{\gamma}$-mediated adipogenesis, whereas PRMT5 knockdown increases lipid accumulation in 3T3-L1 cells. Consistently, PRMT5 attenuates the expression of Lpl and aP2, the target genes of $PPAR{\gamma}$, as demonstrated by RT-qPCR analysis. Overall, these results suggest that PRMT5 interacts with CACUL1 to impair the transcriptional activity of $PPAR{\gamma}$, leading to the inhibition of adipocyte differentiation. Therefore, the regulation of PRMT5 enzymatic activity may provide a clue to develop an anti-obesity drug.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.11a
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• pp.138-138
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• 2001