• Development and Reproduction
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• v.4 no.2
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• pp.221-229
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• 2000

Lactogenesis in mammary gland is under the control of various lactogenic hormones including hypophysial growth hormone and prolactin. Recent studies reported that such pituitary lactogenic hormones are also expressed in mammary cells as well as in pituitary. For the purpose to analyze the role of these non-pituitary hormones in mammary cells, $\beta$ -lactoglobulin (BLG) gene promoter was selected as a model system. The growth hormone suppressed BLG promoter activity when it was applied alone on cultured mammary HCll cells. Along with lactogenic hormones such as insulin, prolactin and glucocorticoid, however, it significantly enhanced expression of BLG promoter activity in a dosage- dependent manner. Exogenous expression of the growth hormone gene in cultured mammary cells also strongly promoted cell proliferation and BLG promoter activity. Bovine growth hormone promoter, on the contrary, did not revealed any notable activity. Above results suggest that endogenous expression of the pituitary hormone genes in mammary cells is not a regulation leakage but a physiological control. Moreover, artificial overproduction of the growth hormone in mammary gland may help increase milk production.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.432-434
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• 1989

• Korean Journal of Animal Reproduction
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• v.27 no.1
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• pp.15-23
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• 2003

Lactadherin (formerly known as BA46), a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and breast carcinomas and may prevent symptomatic rotavirus infections. In this study, under the control of tissue specific and hormonal inducible mouse whey acidic protein (WAP) promote., the expression pattern of lactadherin (Ltd) in lactogenic hormone-dependent mouse mammary epithelial cell line HC11 were tested. pLNWLtd construct containing 2.4 kilobases of the WAP promoter and 1.5 kilobases of human lactadherin gene was stably transfered into HC11 cells using retroviral vector system. Integration and expression level of the transgene was estimated using PCR and RT-PCR, respectively. Prominent induction of Ltd gene under the WAP promoter was accomplished in the presence of insulin, hydrocortisone and prolactin. Compared to the control (cells cultured with insulin alone), however we observed that the WAP promoter was leaky. These data indicate that luther studies are needed in finding an appropriate promoter other than WAP promoter because of its leakiness.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.94-94
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• 2002

Lactadherin (formerly known as BA46), a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and breast carcinomas and may prevent symptomatic rotavirus infections. In this study, under the control of mouse whey acidic protein (WAP) promoter, the expression pattern of lactadherin (Ltd) in lactogenic hormone-dependent mouse mammary epithelial cell line HC11 were tested. pLNWLtd construct containing 2.4 kilobases of the WAP promoter and 1.5 kilobases of human lactadherin gene was stably transfered into HC11 cells using retroviral vector system. Integration and expression level of the transgene was estimated using PCR and RT-PCR, respectively. Prominent induction of Ltd gene under the WAS promoter was accomplished in the presence of insulin, hydrocortisone and prolactin, while induction with insulin alone resulted in lower expression. Our results demonstrate that the expression of the transgene is increased by synergistic effect of several lactogenic hormones, including insulin, hydrocortisone, and prolactin.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.421-427
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• 2012

The production of therapeutic proteins from transgenic animals is one of the most important successes of animal biotechnology. Milk is presently the most mature system for production of therapeutic proteins from a transgenic animal. Specifically, ${\beta}$-casein is a major component of cow, goat and sheep milk, and its promoter has been used to regulate the expression of transgenic genes in the mammary gland of transgenic animals. Here, we cloned the porcine ${\beta}$-casein gene and analyzed the transcriptional activity of the promoter and intron 1 region of the porcine ${\beta}$-casein gene. Sequence inspection of the 5'-flanking region revealed potential DNA elements including SRY, CdxA, AML-a, GATA-3, GATA-1 and C/EBP ${\beta}$. In addition, the first intron of the porcine ${\beta}$-casein gene contained the transcriptional enhancers Oct-1, SRY, YY1, C/EBP ${\beta}$, and AP-1, as well as the retroviral TATA box. We estimated the transcriptional activity for the 5'-proximal region with or without intron 1 of the porcine ${\beta}$-casein gene in HC11 cells stimulated with lactogenic hormones. High transcriptional activity was obtained for the 5'-proximal region with intron 1 of the porcine ${\beta}$-casein gene. The ${\beta}$-casein gene containing the mutant TATA box (CATAAAA) was also cloned from another individual pig. Promoter activity of the luciferase vector containing the mutant TATA box was weaker than the same vector containing the normal TATA box. Taken together, these findings suggest that the transcription of porcine ${\beta}$-casein gene is regulated by lactogenic hormone via intron 1 and promoter containing a mutant TATA box (CATAAAA) has poor porcine ${\beta}$-casein gene activity.

• 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.