• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.448-458
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• 2009

It has been well documented from animal and human studies that conjugated linoleic acid (CLA) has numerous beneficial effects on health. In chickens, CLA exerts many effects on performance ranging from egg quality and yolk lipids to meat quality. Although there are several CLA isomers available, not all CLA isomers have the same incorporation rates into egg yolk: cis-9,trans-11 and trans-10,cis-12 CLA isomers are more favorably deposited into egg yolk than other isomers investigated, but of the two isomers, the former has a higher incorporation rate than the latter. CLA alters the amounts and profiles of lipids in plasma, muscles and liver. Furthermore, increased liver weight was reported in chickens fed dietary CLA. As observed in egg yolk, marked reduction in intramuscular lipids as well as increased protein content was observed in different studies, leading to elevation in protein-to-fat ratio. Inconsistency exists for parameters such as body weight gain, feed intake, feed conversion ratio, egg production rate and mortality, depending upon experimental conditions. One setback is that hard-cooked yolks from CLA-consuming hens have higher firmness as refrigeration time and CLA are increased, perhaps owing to alterations in physico-chemistry of yolk. Another is that CLA can be detrimental to hatchability when provided to breeders: eggs from these breeders have impaired development in embryonic and neonatal stages, and have increased and decreased amounts of saturated fatty acids and monounsaturated fatty acids (MUFAs), respectively. Thus, both problems can be fully resolved if dietary sources rich in MUFAs are provided together with CLA. Emerging evidence suggests that CLA exerts a critical impact on stress and immune functions as it can completely nullify some of the adverse effects produced by immune challenges and reduce mortality in a dose-dependent manner. Finally, CLA is a key regulator of genes that may be responsible for lipid metabolism in chickens. CLA down-regulates both expression of the gene encoding stearoyl-CoA desaturase-1 and its protein activity in the chicken liver while up-regulating mRNA of sterol regulatory element-binding protein-l.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.89-89
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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 CYP1Al. 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.

• 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.

• Molecules and Cells
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• v.43 no.3
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• pp.228-235
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• 2020

The Drosophila transmembrane semaphorin Sema-1a mediates forward and reverse signaling that plays an essential role in motor and central nervous system (CNS) axon pathfinding during embryonic neural development. Previous immunohistochemical analysis revealed that Sema-1a is expressed on most commissural and longitudinal axons in the CNS and five motor nerve branches in the peripheral nervous system (PNS). However, Sema-1a-mediated axon guidance function contributes significantly to both intersegmental nerve b (ISNb) and segmental nerve a (SNa), and slightly to ISNd and SNc, but not to ISN motor axon pathfinding. Here, we uncover three cis-regulatory elements (CREs), R34A03, R32H10, and R33F06, that robustly drove reporter expression in a large subset of neurons in the CNS. In the transgenic lines R34A03 and R32H10 reporter expression was consistently observed on both ISNb and SNa nerve branches, whereas in the line R33F06 reporter expression was irregularly detected on ISNb or SNa nerve branches in small subsets of abdominal hemisegments. Through complementation test with a Sema-1a loss-of-function allele, we found that neuronal expression of Sema-1a driven by each of R34A03 and R32H10 restores robustly the CNS and PNS motor axon guidance defects observed in Sema-1a homozygous mutants. However, when wild-type Sema-1a is expressed by R33F06 in Sema-1a mutants, the Sema-1a PNS axon guidance phenotypes are partially rescued while the Sema-1a CNS axon guidance defects are completely rescued. These results suggest that in a redundant manner, the CREs, R34A03, R32H10, and R33F06 govern the Sema-1a expression required for the axon guidance function of Sema-1a during embryonic neural development.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.257-260
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• 2002

Dissolved oxygen level of cell culture media has a critical effect on cellular metabolism, which governs specific productivity of recombinant proteins and mammalian cell growth However, in the cores of cell aggregates or cell-immobilized beads, oxygen level frequently goes below a critical level. Mammalian cells have a number of genes induced in the lower level of oxygen, and the genes contain a common cis-acting element (-RCGTG-), hypoxia response element (HRE). By binding of hypoxia inducible factor-l (HIF-I) to the HRE, promoters of hypoxia inducible genes are activated, which is a survival mechanism. In this work, to develop a CHO cell capable of producing recombinant proteins in immobilization and high density cell culture efficiently, mammalian expression vectors containing human tissue-type plasminogen activator (t-PA) gene controlled by HRE were constructed and stably transfected into the CHO cells. In $Ba^{2+}$ -alginate immobilization culture, CHO/pCl/dhfr/2HRE-t-PA cells produced 2 folds higher recombinant t-PA activity than CHO/pCl/dhfrlt-PA cells without $CoCl_2$ treatment. Furthermore, in repeated fed batch culture, productivity of t-PA in immobilized CHO/pCI/dhfr/2HRE-t-PA cells was 121 ng/ml/day, total production of 0.968 mg/day at 11 days culture while CHO/pCIIdhfrlt-PA cells was 22.8 ng/ml/day. All these results indicate that HRE is very useful for the enhancement of protein productivity in mammalian cell cultures.

• Korean Journal of Plant Tissue Culture
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• v.28 no.5
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• pp.231-237
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• 2001

A cDNA clone encoding metallothionein-like protein (CitMT45), which was reported by Moriguchi et al. (1998), was isolated from Citrus fruits cDNA library through differential screening. Our cDNA clone has longer 5'untranslated region, compared to it isolated by Moriguchi et al. (1998). RNA blot analysis showed that the mRNA was abundant in fleshes than peels, leaves, and flowers, as a single transcript. However, regardless of tissue types, the blots showed the similar expression patterns in the process of development with some different profile. These results suggest that CitMT45 may play important roles in the development and/or senescence of various tissues of Citrus. A genomic clone corresponding to CitMT45 was isolated and found to have three exons and two introns. A primer extension analysis suggested that the transcription of CitMT45 gene was started at three start sites with different degrees. The 5'-flanking region was shown to contain a putative metal regulatory element (MRE) and low- temperature responsive element which suggests the possibility of metal-and cold-regulated transcription, respectively.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.49-54
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• 1995

To understand the molecular structure and pathogenesis mechanism of Korean garlic viruses, we have isolated cDNA clones for garlic viruses. The partial nucleotide sequences of 24 cDNA clones were determined and those of five clones containing poly(A) tail were compared with sequences of other plant viruses. One of these clones, V9, has a primary structure similar to the carlavirus group, suggesting that the clone V9 derived from a part of garlic latent virus (GLV). Northern blot analysis with the clone V9 as a probe demonstrated that GLV genome is 8.5 knt long and has a poly(A) tail. The clone V9 encodes coat protein (CP) of 33 kDa and nucleic acid binding protein of 10 kDa in different reading frame. The hexanucleotide motif, 5'-ACCUAA, which is conserved in the 3' noncoding region arid was proposed to be a cis-acting element involved in the production of negative strand genomic RNA was noticed. Complementary sequence to the hexanucleotide motif, 5'-TTAGGT, is also found in the positive strand of V9 RNA. The putative CP gene was cloned into the pRSET-A expression vector and expressed in E. coli BL21. The expressed recombinant V9CP protein was purified by $Ni^{2+}$ NTA affinity chromatography. The anti-V9CP antibody recognizes 34 kDa polypeptide which could be CP of GLV in infected garlic leaf extract. Immunoblot and Northern blot analysis of various cultivars shows wide occurrence of GLV in Korean garlic plants.

• Journal of Life Science
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• v.28 no.1
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• pp.37-42
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• 2018

Non-steroidal anti-inflammatory drug-activated gene-1 (NAG-1) is a transforming growth factor beta (TGF-${\beta}$) superfamily gene associated with pro-apoptotic and anti-tumorigenic activities. In the present study, we investigated if caffeic acid phenethyl ester (CAPE) derived from propolis could induce the expression of anti-tumorigenic gene NAG-1. Our results indicate that CAPE significantly induced NAG-1 expression in a time- and concentration-dependent manner in HCT116 cells. We also found that CAPE induced NAG-1 expression in a concentration-dependent manner in another human colorectal cancer cell line, LOVO. In addition, CAPE triggered apoptosis, which was detected with Western blot analysis using poly-(ADP-ribose) polymerase antibody. NAG-1 induction by CAPE was not dependent on transcription factor p53, which was confirmed with Western blot analysis using p53 null HCT116 cells. The luciferase assay results indicated that the new cis-elements candidates were located between -474 and -1,086 of the NAG-1 gene promoter. CAPE dramatically induced activating transcription factor 3 (ATF3) expression, but not cAMP response element-binding protein (CREB), which shares the same binding sites with ATF3. The co-transfection experiment with pCG-ATF3 and pCREB showed that only ATF3 was associated with NAG-1 up-regulation by CAPE, whereas CREB had no effect. In conclusion, the results suggest that CAPE could induce the expression of anti-tumorigenic gene NAG-1 mainly through ATF3.

• Molecules and Cells
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• v.27 no.3
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• pp.279-282
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• 2009

"Two-cysteine" peroxiredoxins are antioxidant enzymes that exert a cytoprotective effect in many models of oxidative stress. However, under highly oxidizing conditions they can be inactivated through hyperoxidation of their peroxidatic active site cysteine residue. Sulfiredoxin can reverse this hyperoxidation, thus reactivating peroxiredoxins. Here we review recent investigations that have shed further light on sulfiredoxin's role and regulation. Studies have revealed sulfiredoxin to be a dynamically regulated gene whose transcription is induced by a variety of signals and stimuli. Sulfiredoxin expression is regulated by the transcription factor AP-1, which mediates its up-regulation by synaptic activity in neurons, resulting in protection against oxidative stress. Furthermore, sulfiredoxin has been identified as a new member of the family of genes regulated by Nuclear factor erythroid 2-related factor (Nrf2) via a conserved cis-acting antioxidant response element (ARE). As such, sulfiredoxin is likely to contribute to the net antioxidative effect of small molecule activators of Nrf2. As discussed here, the proximal AP-1 site of the sulfiredoxin promoter is embedded within the ARE, as is common with Nrf2 target genes. Other recent studies have shown that sulfiredoxin induction via Nrf2 may form an important part of the protective response to oxidative stress in the lung, preventing peroxiredoxin hyperoxidation and, in certain cases, subsequent degradation. We illustrate here that sulfiredoxin can be rapidly induced in vivo by administration of CDDO-TFEA, a synthetic triterpenoid inducer of endogenous Nrf2, which may offer a way of reversing peroxiredoxin hyperoxidation in vivo following chronic or acute oxidative stress.

• Journal of Life Science
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• v.21 no.12
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• pp.1784-1788
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• 2011

The typical miRNA and its nearby host gene are co-expressed by sharing the same promoter. We assumed that miR-7b and its host gene FICT might use an identical promoter for their brain specific gene expression. Sequence comparison of the genomic DNA of mouse miR-7b, human miR-7-3 and their host genes by using the bioinformatic tools revealed high sequence homology and several putative transcription factor-binding sites on the promoter region. In order to probe the hypothesis we used a luciferase vector system into which we cloned the 5' upstream conserved region of miR-7b and FICT. The putative promoter region showed decreased luciferase activity, suggesting that the 5' upstream of miR-7b and FICT contain a negative regulator for gene expression.