• Korean Journal of Microbiology
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• v.47 no.4
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• pp.342-347
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• 2011

T cells play a key role in viral infection. However, in patients with chronic hepatitis C virus (HCV) infection, HCV-specific T cells are dysfunctional and impaired in the liver, which is the primary site for HCV replication. There are multiple potential mechanisms for HCV-specific T cell dysfunction including induction of immune inhibitory pathways (program death-1; PD-1, cytotoxic t lymphocyte associated antigen-4; CTLA-4) and immune tolerance induced specific for the liver. However, the interaction between hepatocytes and HCV-specific CD8 T cells has not clearly established. In this study, we confirmed huh (human hepatoma) 7.5 cells expressing HLA (human leukocyte antigen) A2 presented antigen to activate HCV-specific CD8 T cells in HLA A2-restricted manner and expression of PD-L (program death ligand) 1 on huh7.5 cells reduced HCV-specific CD8 T cell activation, suggesting an immune modulatory activity. Loss of HCV-specific tetramer responses following antigenic stimulation correlated with increased caspase-3 activity. In addition, PD-L1 on huh7.5 cells rescued HCV-specific CD8 T cells from apoptosis. Our results suggest that the interaction between PD-L1 and PD-1 can recover the function of HCV-specific CD8 T cells in the liver, which could be applied in therapy of HCV chronic infection.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.855-862
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• 2010

Among the known interferon-induced antiviral mechanisms, the Mx pathway is one of the most powerful pathways. The Mx protein has direct antiviral activity and inhibits a wide range of viruses by blocking an early stage of the viral replication cycle. Cloning, characterization, and expression of Mx in vivo and in vitro have been conducted. The chicken Mx gene spans 21 kb and is made up of 14 exons and 13 introns, of which the promoter region was analyzed. The real-time PCR results showed that Mx expression was increased in chicken embryo fibroblasts (CEF) after 12- and 24-h induction with polyI: C. Induction of Mx expression by poly I: C in vivo revealed tissue-specific patterns among the chicken tissues tested. A trace expression of Mx was detected in healthy chicken liver tissues from adult chickens without inducement; the expression levels in the liver, heart, and gizzard were higher than in the muscle and kidney. This is the first report to demonstrate the expression of a glutathione-S-transferase-tagged-Mx fusion protein of 75 KDa, as well as the biological activity tested by SDS-PAGE and western blotting.

• Proceedings of the Korean Society of Toxicology Conference
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• 2000.11a
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• pp.31-41
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• 2000

The major issue in the post genome sequencing era is determination of gene expression patterns in variety of biological systems. A microarray system is a powerful technology for analyzing the expression profile of thousands of genes at one experiment. In this study, we constructed cDNA microarray which carries 2,304 cDNAS derived from oligo-capped mouse cDNA library. Using this hand-made microarray we determined gene expression in various biological systems. To determine tissue specific genes, we compared Nine genes were highly-expressed in adult mouse brain compared to kidney, liver, and skeletal muscle. Tissue distribution analysis using DNA microarray extracted 9 genes that were predominantly expressed in the brain. A database search showed that five of the 9 genes, MBP, SC1, HiAT3, S100 protein-beta, and SNAP25, were previously known to be expressed at high level in the brain and in the nervous system. One gene was highly sequence similar to rat S-Rex-s/human NSP-C, suggesting that the gene is a mouse homologue. The remaining three genes did not match to known genes in the GenBank/EMBL database, indicating that these are novel genes highly-expressed in the brain. Our DNA microarray was also used to detect differentiation specific genes, hormone dependent genes, and transcription-factor-induced genes. We conclude that DNA microarray is an excellent tool for identifying differentially expressed genes.

• Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.88-97
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• 2008

Lipoproteins are complexes of lipids and specific apolipoproteins that are involved in lipid transport and redistribution among various tissues. In this study, we isolated full-length apolipoprotein cDNA sequences encoding apolipoprotein A-I (apoA-I), apoE, apoC-II, and apo-14 kDa in barred knifejaw, Oplegnathus fasciatus. In addition, we reconstructed phylogenetic trees and investigated mRNA tissue distributions. Alignment analyses of amino acid sequences revealed that secondary structures of the polypeptides apoA-I, apoE, and apoC-II in barred knifejaw are well conserved with their teleostean and mammalian counterparts in terms of characteristic tandem repetitive units forming amphipathic ${\alpha}$-helices. Both the sequence alignment data and cleavage sites of apo-14 kDa indicated a clear differentiation between Percomorpha and Cypriniformes. Meanwhile, the phylogenetic trees of apolipoprotein sub-families suggested that the common ancestor prior to the split of the Actinopterygii (ray-finned fishes) and Sarcopterygii (tetrapods) would have possessed the primordial protein-encoding genes. Tissue distribution of each apolipoprotein transcript determined by semi-quantitative RTPCR showed that barred knifejaw apoA-I transcripts were more or less ubiquitously expressed in the liver, intestines, brain, muscle, spleen, and kidney. The most striking difference from previous observations on barred knifejaw was the ubiquitous expression of apoE across all somatic tissues. Barred knifejaw apoC-II showed tissue-specific expression in the liver and intestines, while the liver and brain were the major sites of apo-14kDa mRNA synthesis.

• BMB Reports
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• v.29 no.2
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• pp.146-150
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• 1996

A 2.1 kb cDNA clone for rat transketolase was isolated from rat liver ${\lambda}gt11$ cDNA library and its sequence was determined. The predicted rat transketolase (655 amino acids with $M_r$ 71,186) is highly similar (92%) to that of the human enzyme except that it contains an extra 32 amino acids at its N-terminus. Although it is less similar (<27%) to transketolases from non-mammalian species, the functional motifs such as the catalytic sites and thiamine binding domain are well conserved in the rat enzyme. Southern blot analysis of genomic DNA verified that transketolase appears to be derived from a single gene. Immunoblot and Northern blot analyses suggested that hepatic transketolase was activated pretranslationally by a 2.1-fold while little change was observed in brain enzyme, indicating a tissue-specific pretranslational activation during postnatal development.

• Biomedical Science Letters
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• v.6 no.3
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• pp.171-179
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• 2000

The lengths of thick and thin filaments in the sarcomeres of most vertebrate skeletal muscles are precisely regulated and are important structural parameters in understanding muscle contraction. Nebulin is a usually large protein that spans the whole length of thin filaments in the sarcomeres of skeletal muscles. In this paper we used SDS-PAGE and immunoblot to identify nebulin isoform proteins in muscle and non-muscle tissues. We prepared embryonic chicken tissues including skeletal muscle, cardiac muscle, smooth muscle, brain, liver to compare nebulin isoform proteins. The proteins were divided into soluble and insoluble fraction. As a result, we identified tissue specific expression of various nebulin isoform proteins in muscle and non-muscle tissues of chicken. Nebulin was detected in skeletal muscle of adult chicken about 500 kDa. Nebulett was expressed in cardiac muscle of embryonic and adult chicken about 107 kDa. A giant protein with molecular mass of about 380 kDa was identified in brain of non-muscle of chicken. This giant protein was detected in the soluble fraction of chicken embryo. The unequal distribution of the nebulin isoform proteins suggests tissue specific regulation of the isoform expression and indicates a functional specialization of the encoded isoform subtypes.

• BMB Reports
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• v.56 no.7
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• pp.374-384
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• 2023

Fibrosis is a pathological condition that is characterized by an abnormal buildup of extracellular matrix (ECM) components, such as collagen, in tissues. This condition affects various organs of the body, including the liver and kidney. Early diagnosis and treatment of fibrosis are crucial, as it is a progressive and irreversible process in both organs. While there are certain similarities in the fibrosis process between the liver and kidney, there are also significant differences that must be identified to determine molecular diagnostic markers and potential therapeutic targets. Long non-coding RNAs (lncRNAs), a class of RNA molecules that do not code for proteins, are increasingly recognized as playing significant roles in gene expression regulation. Emerging evidence suggests that specific lncRNAs are involved in fibrosis development and progression by modulating signaling pathways, such as the TGF-β/Smad pathway and the β-catenin pathway. Thus, identifying the precise lncRNAs involved in fibrosis could lead to novel therapeutic approaches for fibrotic diseases. In this review, we summarize lncRNAs related to fibrosis in the liver and kidney, and propose their potential as therapeutic targets based on their functions.

• Animal Bioscience
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• v.34 no.2
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• pp.172-184
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• 2021

Objective: Vanin1 (VNN1) is a pantetheinase that can catalyze the hydrolysis of pantetheine to produce pantothenic acid and cysteamine. Our previous studies showed that VNN1 is specifically expressed in chicken liver. In this study, we aimed to investigate the roles of peroxisome proliferators activated receptor α (PPARα) and miRNA-181a-5p in regulating VNN1 gene expression in chicken liver. Methods: 5'-RACE was performed to identify the transcription start site of chicken VNN1. JASPAR and TFSEARCH were used to analyze the potential transcription factor binding sites in the promoter region of chicken VNN1 and miRanda was used to search miRNA binding sites in 3' untranslated region (3'UTR) of chicken VNN1. We used a knock-down strategy to manipulate PPARα (or miRNA-181a-5p) expression levels in vitro to further investigate its effect on VNN1 gene transcription. Luciferase reporter assays were used to explore the specific regions of VNN1 targeted by PPARα and miRNA-181a-5p. Results: Sequence analysis of the VNN1 promoter region revealed several transcription factor-binding sites, including hepatocyte nuclear factor 1α (HNF1α), PPARα, and CCAAT/enhancer binding protein α. GW7647 (a specific agonist of PPARα) increased the expression level of VNN1 mRNA in chicken primary hepatocytes, whereas knockdown of PPARα with siRNA increased VNN1 mRNA expression. Moreover, the predicted PPARα-binding site was confirmed to be necessary for PPARα regulation of VNN1 gene expression. In addition, the VNN1 3'UTR contains a sequence that is completely complementary to nucleotides 1 to 7 of miRNA-181a-5p. Overexpression of miR-181a-5p significantly decreased the expression level of VNN1 mRNA. Conclusion: This study demonstrates that PPARα is an important transcriptional activator of VNN1 gene expression and that miRNA-181a-5p acts as a negative regulator of VNN1 expression in chicken hepatocytes.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.1
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• pp.13-29
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• 2020

Objectives This study was performed to decide the bone union effect of Hwaweo-jeon on tibia fractured mice. Methods In this study, laboratory experiments were implemented by the stage of in vitro and in vivo. In in vitro, MC3T3-E1 cells were treated with various concentration of Hwaweo-jeon extract (HWJ). To investigate effect of HWJ for osteoblast, relative mRNA expression of 5 substances (alkaline phosphatase [ALP], runt-related transcription factor 2 [Runx2], osteocalcin [OCN], osterix [OSX] and collagen type II alpha 1 chain [Col2a1]) was used as a marker of osteogenesis. In order to determine HWJ's effect for fracture healing, relative gene expression level of ALP, Runx2, OCN, OSX and Col2a1 were used to find out the influence to osteoblast. Furthermore, receptor activator of nuclear factor kappa-B ligand and osteoprotegerin relative mRNA expression were used to estimate the impact to osteoclast. Also, X-ray was used for the purpose of identifying bone union in tibia-fracture mouse model. Results In in vitro experiment, most part of relative mRNA expression were increased compared to control group. In in vivo and in vitro experiment, HWJ induced osteoblast activitation by verifying relative mRNA expression of 5 substances. And in vivo experiment, we can also identify that HWJ triggered osteoclast activation during early stage of tibia fracture. Furthermore, X-ray pictures show noticeable recovery of tibia fracture. Conclusions HWJ extract promotes bone union by facilitating the osteoblast. But, HWJ may occur liver & kidney toxicity over specific concentration. Therefore, when HWJ is applied to human body, doctors have to follow up the liver function test & renal function test of patient.

• Environmental Mutagens and Carcinogens
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• v.24 no.4
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• pp.171-179
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• 2004

Cytochrome P4503A4(CYP3A4) is the most abundnat CYPs in human liver, comparising approximately 30% of the total liver CYPs contents ans is involbed in the metabolism of more than 60% of currently used therapeutic drugs. The expression of CYP3A4 is induced by a variety of structurally unrelated xonobiotics including the antibiotic rifampicin and endogenous hormones, and might be mediated through steroid and xenobiotic receptor(SXR) system. The molecular mechanisms underlying regulation of CYP3A4 gene expression hae not been understood. In order to gain the insight of the molecular mechanism of CYP3A4 gene expression, study has been undertaken to investigate if the histone deacelylation is involved in the regulation of CYP3A4 gene expression by proximal promoter or not. Also SXR was investigated to see if they were involved in the regulation of CYP3A4 proximal promoter activity. HepG2 or Hena-I cells were transfected with a plasmid containing~1kb of the CYP3A4 proximal promoter region (-863 to +64bp) cloned in front of a reporter gene, luciferase, in the presence or absence of SXR or hER. Transfected cells were treated with CYP3A4 inducers such as rifampicin, PCN and RU 486, or with estradiol, in order to exmine to regulation of CYP3A4 gene expression in the presence or absence of trichostatin A (TSA). In HepG2 cells, CYP3A4 inducers and estradiol increased significantly the luciferase activity by CYP3A4 proximal promoter, only when TSA was co-treated after SXR cotransfection. In the case of Hepa-I cells CYP3A4 inducers and estradiol incressed modestly the luciferase activity when TSA was co-treated, but this increment was not enhanced by SXR cotransfection in contrast to HepG2 cells. Taken together, these results indicated that the inhibition of histone deacetylation was required to SXR-mediated increase in CYP3A4 proximal promoter region when rifampicin, or PCN was treated. Futher a trans-activation by SXR may demand other species-specific transcription factors.