• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.768-774
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• 2007

To study the effect of dietary docosahexaenoic acid (DHA) enrichment on the expression of hepatic genes in pigs, weaned, crossbred pigs (30 d old) were fed diets supplemented with either 2% tallow or DHA oil for 18 d. Hepatic mRNA was extracted. Suppression subtractive hybridization was used to explore the hepatic genes that were specifically regulated by dietary DHA enrichment. After subtraction, we observed 288 cDNA fragments differentially expressed in livers from pigs fed either 2% DHA oil or 2% tallow for 18 d. After differential screening, 7 genes were found to be differentially expressed. Serum amyloid A protein 2 (SAA2) was further investigated because of its role in lipid metabolism. Northern analysis indicated that hepatic SAA2 was upregulated by dietary DHA enrichment (p<0.05). In a second experiment, feeding 10% DHA oil for 2d significantly increased the expression of SAA2 (compared to the 10% tallow group; p<0.05). The porcine SAA2 full length cDNA sequence was cloned and the sequence was compared to the human and mouse sequences. The homology of the SAA2 amino acid sequence between pig and human was 73% and between pig and mouse was 62%. There was a considerable difference in SAA2 sequences among these species. Of particular note was a deletion of 8 amino acids, in the pig compared to the human. This fragment is a specific characteristic for the SAA subtype that involved in acute inflammation reaction. Similar to human and mouse, porcine SAA2 was highly expressed in the liver of pigs. It was not detectable in the skeletal muscle, heart muscle, spleen, kidney, lung, and adipose tissue. These data suggest that SAA2 may be involved in mediation of the function of dietary DHA in the liver of the pig, however, the mechanism is not yet clear.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.75-75
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• 2002

The present study was conducted for the production of transgenic cloned cows by somatic cell nuclear transfer (SCNT) that secrete human prourokinase into milk. To establish an efficient production system for bovine transgenic SCNT embryos, the offset was examined of various conditions of donor cells including cell type, size, and passage number on the developmental competence of transgenic SCNT embryos. An expression plasmid far human prourokinase (pbeta-ProU) was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and a human prourokinase target gene into a pcDNA3 plasmid. Three types of bovine somatic cells including two adult cells (cumulus cells and ear fibroblasts) and fetal fibroblasts were prepared and transfected using a lipid-meidated method. In Experiment 1, developmental competence and rates of GFP expression in bovine transgenic SCNT embryos reconstructed with cumulus cells were significantly higher than those from fetal and ear fibroblasts. In Experiment 2, the effect of cellular senescence in early (2 to 4) and late (8 to 12) passages was investigated. No significant differences in the development of transgenic SCNT embryos were observed. In Experient 3, different sizes of GFP-expressing transfected cumulus cells [large (>30 ${\mu}{\textrm}{m}$) or small cell (<30 ${\mu}{\textrm}{m}$)] were used for SCNT. A significant improvement in embryo development and GFP expression was observed when small cumulus cells were used for SCNT. Taken together, these results demonstrate that (1) adult somatic cells could serve as donor cells in transgenic SCNT embryo production and cumulus cells with small size at early passage were the optimal cell type, and (2) transgenic SCNT embryos derived from adult somatic cells have embryonic development potential.

• BMB Reports
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• v.37 no.4
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• pp.402-407
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• 2004

A human gene T-complex protein 10 like (TCP10L) was cloned in our lab. A previous study showed that it expressed specifically in the liver and testis. A transcription experiment revealed that TCP10L was a transcription factor with transcription inhibition activity. In this study, the human MAD4 was identified to interact with TCP10L by a yeast two-hybrid screen. This finding was confirmed by immunoprecipitation and subcellular localization experiments. As MAD4 is a member of the MAD family, which antagonizes the functions of MYC and promotes cell differentiation, the biological function of the interaction between TCP10L and MAD4 may be to maintain the differentiation state in liver cells. Also, we propose that the up-regulation of Myc is caused by the down-regulation of TCP10L in human hepatocarcinomas.

• Biomolecules & Therapeutics
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• v.10 no.2
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• pp.78-84
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• 2002

Taurine (2-ethaneaminosulfonic acid, $^+{NH}_3{CH_2}{CH_2}{SO_3^{-}}$) is endogenous amino acid with functions as modulator of osmoregulation, antioxidation, detoxification, transmembrane calcium transport, and a free radical scavenger in mammalian tissues. Taurine transporter(TAUT) contains 12 transmembrane helices, which are typical of the $Na^+$- and $Cl^-$-dependent transporter gene family, and has been cloned recently from several species and tissues. To analyze the expression of TAUT mRNA, one step RT-PCR was performed from human and mouse cultured cell lines and from various mouse tissues. The primers were designed to encode highly conserved amino acid sequences at the second transmembrane domain and at the fourth and fifth intracellular domains. RT-PCR analysis showed both of the human intestine HT-29 and mouse macrophage RAW264.7 cell lines expressed mRNA of TAUT. To define the expression patterns of the TAUT mRNA in the murine organs, RT-PCR was performed to detect cDNA representing TAUT mRNA from seven different mouse tissues. The TAUT was detected in all of the mouse tissues analyzed such as heart, lung, thymus, kidney, liver, spleen and brain. A large amount of transcript was fecund from heart, liver, spleen, kidney, and brain, while lung contained a very small amount of transcript.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.318-322
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• 1999

A new baculovirus transfer vector (pPGP404) was constructed to increase the expression level of human thrombopoietin (hTPO) in insect cells. In pPGP404, hTPO was cloned next to the AcNPV polyhedrin-gp64 dual promoter and the leader sequence of hTPO was substituted with that of gp64. A recombinant baculovirus, AcPGP404, was constructed by using pPGP404 as a transfer vector. hTPO was expressed in AcPGP404-infected TN5 cells and it was observed that the expression levels of hTPO in TN5 cells increased three-fold ($6.0 {\mu}g/ml^{-1}$) compared to the level expressed under the control of the polyhedrin single promoter. These results indicate that the polyhedrin-gp64 dual promoter system would be useful for expression in large quantities of recombinant proteins in insect cells.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.59-59
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• 2003

Serotonin (5-HT; 5-hydroxytryptamine) exerts multiple effects on central nervous system as well as behaviors such as mood and appetite. The signaling of serotonin is mediated by 7 families of serotonin receptors, designated 5-HT$_1$ to 5-HT$_{7}$. Six families of this receptor are G-protein coupled 7TM receptors, and the third intracellular loop of these receptors is proposed to interact with specific types of G-proteins. To investigate the specific interaction between the third intracellular loop of 5-HT$_{6}$ with G$\square$s, we have constructed a chimera protein that represent the third intracellular loop of 5-HT$_{6}$ within a leucine zipper motifs, In addition an alpha subunit of human G-protein that interact with 5-HT$_{6}$ was cloned into a bacterial expression vector. The two proteins were expressed in E. coli and purified in homogeneity. The interaction of the prepared proteins was examined by ELISA assay. The affinity between the two proteins and effect of insertion mutations were discussed.ussed.d.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.151-160
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• 1997

In view of the potential of replicase protein as a diagnostic reagent for human caliciviruses (HuCVs), we have cloned and over-expressed this gene from the Snow Mountain-like Korean strains in Escherichia coli as a fusion protein with glutathione S-transferase (GST), and described the preliminary antigenic characterization of the recombinant products. Each 470bp fragment corresponding to highly conserved region of RNA-dependent RNA polymerase was generated by RT-PCR from stools of two diarrheal children, cloned in pMOSBlue T-vector, and subcloned between the EcoRI and SalI restriction sites of pGEX-4T-3, a GST gene fusion vector, yielding $pGCV_{pol}$. This construct expressed a Snow Mountain-like HuCV replicase under the control of the IPTG-inducible tac promoter. An extract prepared by sonication of the E. coli cell inclusion bodies bearing $pGCV_{pol}$ products was purified and analyzed by SDS-PAGE. After Coomassie blue staining, it was shown that the recombinant replicase migrated on the gels with an approximate molecular mass of 46.5 kDa, that was subsequently cleaved into a 26 kDa GST fragment and a 20.5 kDa replicase protein upon digestion with thrombin protease. The replicase was recognized on immunoblotting with the sera from symptomatic children with the HuCV-associated diarrhea but not by asymptomatic sera from adults. The results presented the first biological activity of individually expressed HuCV replicase subunit and provided important reagents for diagnosis of HuCV infection.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.329-334
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• 2006

Adipocyte-specific secretory factor (ADSF)/resistin, a hormone, is a small cysteine-rich protein secreted from adipose tissue and has been implicated in modulating adipogenesis in humans and rodents. The objective of this study was to clone a gene encoding ADSF/resistin and to characterize its function in Korean Native Cattle (Hanwoo). The coding sequence was 330 base pairs and it encoded a protein of 109 amino acids. An NCBI BLAST-search revealed the cloned cDNA fragment shared significant homology (82%) with the cDNA encoding the human ADSF/resistin. The nucleotide sequence homology of the Hanwoo sequence was 73% and 64% for the rat and mouse, respectively. A 654 bp ADSF/resistin gene promoter was cloned and putative binding sites of transcription factors were identified. Tissue distribution of ADSF mRNA was examined in liver, skeletal muscles (tenderloin, biceps femoris), subcutaneous fat, and perirenal fat by RT-PCR. ADSF mRNAs were detected in fat tissues but not in liver and muscles, suggesting that ADSF/resistin expression may be induced during adipogenesis. Although, the physiological function of ADSF/resistin in the cow remains to be determined, these data indicate ADSF is related to the adipocyte phenotype and may have a possibly regulatory role in adipocyte function.

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.299-304
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• 1997

Expression in the periplasm of Escherichia coli of cloned heavy and light chain cDNAs for Fab fragment of a murine monoclonal antibody MabB9 (${\gamma}2b$, K), specific for human plasma apolipoprotein B-100 of LDL, was studied. For the purpose, a vector for two-cistronic expression of the heavy chain cDNA, at the 5' terminus, and light chain cDNA, at the 3' terminus, was constructed using the signal sequences, pelB (for heavy chain) and ompA (for light chain) in a pET vector system. The constructed vector was transformed into E. coli BL21(DE3). The expressed heavy chain (25 kDa) and light chain (23 kDa) of the antibody molecule were detected in total cell extracts as well as in the periplasmic extracts of E. coli.

• Korean Journal of Animal Reproduction
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• v.25 no.3
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• pp.277-286
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• 2001

Improvement and possible commercialization of a home-made electroporation apparatus(home-made) were further tried to establish a simple and effective introduction of foreign gene into sperm followed by in vitro fertilization. Expressions of introduced pJJ9 and pNT plasmids were shown in all fertilized eggs with electroporated spermatozoa. In particular, with this gene transfer system all the fry showed a consistently transient expression in the syncytium of the yolk sac. This fact is important since some required, minute quantity of human proteins can be produced from the established transient expression on the yolk sac of all fry derived from in vitro fertilization with electroporated spermatozoa. To explore tissue-specific expression in fish, which we will use a similar system later, we targeted the nerve tissue to see whether tissue-specific promoter is working in fish properly. pNT plasmid containing a nerve cell-specific tubulin promoter gene demonstrated consistently exact targeted expressions among the developing nerve cells in later stages of embryos and hatched fry. Finally, liver-specific genes are now being cloned by using already selected primers for useful human protein gene fusion.