• Journal of the Society of Cosmetic Scientists of Korea
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• v.21 no.1
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• pp.53-66
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• 1995

The gene for ${\gamma}$-casein, a milk protein, is a member of a family of casein gene which is expressed in mammary glands of the animal during the late gestation and lactation periods binder the influence of various hormones. In order to elucidate tile mechanisms b)'which hormones regulate the coordinate induction of milk protein genes, the mouse ${\gamma}$-casein gene was isolated and characterized. The ${\gamma}$-casein gene was screened from a mouse genomic library constructed in bacteriophage EMBL3 with the ${\gamma}$-casein CDNA used as probe and one clone was obtained. The ${\gamma}$-casein CDNA as probe was partially sequenced and contained ATG start codon and 5'-noncoding region. The cloned genomic DNA was digested with Sal I restriction enzyme, by which the insert DNA can be isolated from EMBL3 vector. Three DNA bands were observed and the size of DNAs was approximately 28kb, 14kb and 9Kb, respectively Accordingly the size of the insert DNA was calculated with approximately 23Kb. The result of Southern blot analysis, however, showed that the cloned genomic DNA was not hybridized with the synthetic oligonucleotides (40 mer) of cDNA 5'-end region, but it was hybridized with the y -casein CDNA. This means that tile cloned y -casein gene may not contain its promoter region. The ${\gamma}$ -casein genomic DNA containing the promoter region has been screening from mouse genomic library with oligonucleotides of CDNA 5'-end region as probe, and twenty-nine clones was obtained.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.212-212
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• 2004

Collagen has been widely studied for medical applications. Previous studies have shown that the bovine β-casein promoter were able to drive cell-specific and hormone-dependent expression to a mouse mammary cell line but failed to induce accurate expression to the mammary gland. of transgenic mice. (omitted)

• Reproductive and Developmental Biology
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• v.40 no.1
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• pp.7-13
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• 2016

Effectiveness of transgene transfer into genome is crucially concerned in mass production of the bio-pharmaceuticals using genetically modified transgenic animals as a bioreactor. Recently, the mammary gland has been considered as a potential bioreactor for the mass production of the bio-pharmaceuticals, which appears to be capable of appropriate post-translational modifications of recombinant proteins. The mammary gland tissue specific vector system may be helpful in solving serious physiological disturbance problems which have been a major obstacle in successful production of transgenic animals. In this study, to minimize physiological disturbance caused by constitutive over-expression of the exogenous gene, we constructed new retrovirus vector system designed for mammary gland-specific expression of the hEPO gene. Using piggyBac vector system, we designed to express hEPO gene under the control of mammary gland tissue specific and lactogenic hormonal inducible goat ${\beta}$-casein or mouse Whey Acidic Protein (mWAP) promoter. Inducible expression of the hEPO gene was confirmed using RT-PCR and ELISA in the mouse mammary gland cells treated with lactogenic hormone. We expect the vector system may optimize production efficiency of transgenic animal and reduce the risk of global expression of transgene.

• Animal Bioscience
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• v.36 no.10
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• pp.1488-1498
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• 2023

Objective: α_S1-Casein is more closely associated with milk allergic reaction than other milk protein components. microRNA (miRNA) is a class of small non-coding RNAs that modulate multiple biological progresses by the target gene. However, the post-transcriptional regulation of α_S1-casein expression by miRNA in ruminants remains unclear. This study aims to explore the regulatory roles of miR-380-3p on α_S1-casein synthesis in goat mammary epithelial cells (GMEC). Methods: α_S1-Casein gene and miR-380-3p expression was measured in dairy goat mammary gland by quantitative real-time polymerase chain reaction (qRT-PCR). miR-380-3p overexpression and knockdown were performed by miR-380-3p mimic or inhibitor in GMEC. The effect of miR-380-3p on α_S1-casein synthesis was detected by qRT-PCR, western blot, luciferase and chromatin immunoprecipitation assays in GMEC. Results: Compared with middle-lactation period, α_S1-casein gene expression is increased, while miR-380-3p expression is decreased during peak-lactation of dairy goats. miR-380-3p reduces α_S1-casein abundance by targeting the 3'-untranslated region (3'UTR) of α_S1-casein mRNA in GMEC. miR-380-3p enhances β-casein expression and signal transducer and activator of transcription 5a (STAT5a) activity. Moreover, miR-380-3p promotes β-casein abundance through target gene α_S1-casein, and activates β-casein transcription by enhancing the binding of STAT5 to β-casein gene promoter region. Conclusion: miR-380-3p decreases α_S1-casein expression and increases β-casein expression by targeting α_S1-casein in GMEC, which supplies a novel strategy for reducing milk allergic potential and building up milk quality in ruminants.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.190-190
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• 2004

Tissue plasminogen activator (tPA) plays important roles in the brain after excitotoxic injury. This study was conducted to produce transgenic pig harboring human tissue plasminogene activator (htPA) gene. Recombinent htPA(rhtPA) genes containing bovine-β-casein promoter (bBC) were prepared for microinjection and testified the expression level of htPA protein from the Chinese hamster ovary (CHO) cell lines before NDA microinjection into the porcine pronuclei. (omitted)

• Korean Journal of Animal Reproduction
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• v.21 no.1
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• pp.1-7
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• 1997

Recently the production of transgenic animals to express foreign proteins in mammary glands has been a routine procedure. However, it still takes a considerable time and effort, and is faced with various technical challenges until the protein of interest is successfully made. Thus, a development of an a vitro model for mamm a ary-specific gene expression for recombinant genes was carried out in this study. To this end, bovine $\alpha$$_S1$ casein cDNA was inserted at the multiple cloning site of pMSG vector under the control of MMTV promoter. MCF$_7$ cells were tran sfected with pMSG $\alpha$$_S1$ CN by CaP0$_4$ precipitation. Transfectants were selected in HAT medium and induced with dexamethasone. The cells were analyzed with chicken anti-casein and FITC-labeled rabbit anti-chicken antibodies. The results showed that dexamethasone induced 30-40 fold increase in the MMTV- $\alpha$$_S1$ casein e expression. Therefore MCF$_7$ cells, which have multiple steroid receptors, along with pMSG vector can be used as an in vitro model for the study of mammary-specific gene expression.

• Korean Journal of Animal Reproduction
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• v.22 no.3
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• pp.237-244
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• 1998

To investigate the fidelity of transgene transmission and expression, we produced transgenic mice carrying bovine $\beta$-casein/bovine grwoth hormone(bGH) fusion gene and examined transmission efficiency and expression level of the transgene in the founders and their progeny. The transgene was composed of 1.8 kb bovine $\beta$-casein promoter and 2.1 kb bGH gene. Ten transgenic mice were produced. Milk and mammary gland were collected from eight transgenic lines at 10-day lactation and a, pp.ied to Western and Northern blot analyses. The bGH expression was detected in four of them. The concentrations of bGH in milk were highly variable from 4$\mu\textrm{g}$/ml to 600$\mu\textrm{g}$/ml depending on the lines. The bGH mRNA level in mammary gland was closely correlated with the bGH concentration in milk in each transgenic line. These results indicated that bGH transgene expression was a, pp.opriately regulated in the mammary gland and secreted into milk in transgenic mice. By using two transgenic lines(#2, #7) secreting a considerable amoung of bGH into their milk, the inferitance and maintenance of transgenic phenotype were assessed in successive four generations. The mean transmission frequencies of transgene in lines #2 and #7 were 34% and 40%, respectively. The bGH concentration in milk were 80, 240, 120, 60$\mu\textrm{g}$/ml in each G0(generation 0), G2, G3, G4 generation of line #2 and 600, 1600, 860, 900$\mu\textrm{g}$/ml in each G1. G2, G3, G4 generation of line #7. These results demonstrated that bovine $\beta$-casein/bGH gene was stably transmitted from generation to generation in a Menelian fashion in trasgenic mice and consistenly expressed in their milk throughout the generations, although there was a little variation in the transmission frequency and expression level of the transgene between generations.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.87-87
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• 2002

Previously, we observed high level expression of goat β-casein/genomic hGH fusion gene in mammary gland of transgenic mice. To develop an expression vector to make a human granulocyte-colony stimulating factor (hG-CSF) protein efficiently produced in milk of transgenic animals, we designed a new bicistronic vector using the goat β-casein/genomic hGH fusion gene as regulation sequences for expression and internal ribosome entry site (IRES) as a mediator for second gene expression. This vector was constructed by insertion of encephalomyocarditis virus (EMCV) IRES-dependent second gene region coupled with hG-CSF cDNA into 3' untranslated region of an intact hGH gene. By microinjcetion, four transgenic mice were generated and three of them transmitted the bicistronic vector to their progeny. (omitted)

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.275-275
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• 2005

• BMB Reports
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• v.28 no.1
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• pp.57-61
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• 1995

The expression of a recombinant human lactoferrin is reported in mouse HC11 mammary epithelial cells. Expression of human lactoferrin (hLF) was achieved by placing its cDNA under the control of the bovine ${\beta}$-casein gene. To improve the hLF expression level in a cell culture system, two artificial introns were also introduced to construct expression vectors. One intron was a hybrid-splice signal consisting of bovine ${\beta}$-casein intron 1 and rabbit ${\beta}$-globin intron II. The other intron was a DNA fragment spanning intron 8 of the bovine ${\beta}$-casein gene. The hybrid intron moderately elevated hLF expression, whereas intron 8 alone did not express any detectable amount of hLF as judged by Northem and Western blot analyses. When the two introns were used together they contributed to a synergistic elevation of hLF expression. These data indicate that artificial introns on both sides of the hLF cDNA were necessary to increase expression of cDNA.