• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.85-85
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• 2003

Human lactoferrin (hLF) is an 80 kDa iron-binding glycoprotein that is expressed in high concentration in milk and in lesser amount in the secondary or specific granules of neutrophils and in plasma, LF is classically considered to be related to the binding, transport, and storage of iron. The transgenic mice carrying the human hLF gene in conjunction with the bovine $\beta$-casein promoter produced the human hLF in their milk during lactation. To screen transgenic mice, PCR was carried out using chromosomal DNA extracted from tail or toe tissues. In this study, stability of germ line transmission and expression of hLF were monitored up to generation Fl7 of a transgenic line. When female mouse of generation F9 was crossbred with normal male, generation F9 to Fl7 mice showed similar transmission rates ($66.0 \pm 12.57%, 42.0 \pm 14.98%, 72.2 \pm 25.45%, 50.0 \pm 16.70%, 65.7 \pm 6.45%, 48.6 \pm 14.65%, 54 1 \pm 18 11%, 57.8 \pm 16.16% and 48.6 \pm 20.66$, respectively), implying that the hLF gene can be transmitted stably up to long term generation in the transgenic mice For ELISA analysis, hLF expression levels were determined with an hLF ELISA kit in accordance with the supplier's protocol. Expression levels of human hLF from milk of generation F9 to Fl3 mice were $ 3.2 \pm 0.69 mg/ml, 3.1 \pm 0.81 mg/ml, 4.6 \pm 1.38 mg/ml, 3.1 \pm 0.42 mg/ml, and 4.5 \pm 1,48 mg/ml$, respectively. These expression levels were lower than that of founder (6.6 mg/$m\ell$) mouse. We concluded that transgenic mice faithfully passed the transgene on their progeny and successively secreted target proteins into their milk through several generations.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.109-110
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• 2003

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.111-112
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• 2006

• Journal of Embryo Transfer
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• v.27 no.4
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• pp.205-209
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• 2012

Transgenic rats and mice are useful experimental animal models for medical research including human disease model studies. Somatic cell nuclear transfer (SCNT) technology is successfully applied in most mammalian species including cattle, sheep, pig and mouse. SCNT is also considered to increase the efficacy of transgenic/knockout mouse and rat production. However, in the area of reproductive biotechnology, the rodent model is inadequate because of technical obstacles in manipulating the oocytes including intracytoplasmic sperm injection and SCNT. In particular, success of rat SCNT is very limited so far. In this review, the history of rodent cloning is described.

• Korean Journal of Animal Reproduction
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• v.17 no.4
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• pp.375-383
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• 1994

The human growth hormone (hGH) gene uder the control of the rat $\beta$-casein promoter gene was designed to produce transgenic mouse expressed hGH gene in only mammary gland. One hundred seventy two eggs microinjected were transferred to the oviducts of pseudopregnants and 43 offspring were delivered. By Southern blotting hybridization, 3 were transgenic with rat $\beta$-casein/hGH gene. The copy numbers of three transgenic founder were 1, 5, and 15, respectively. A radioimmunoassay was developed to quantitate the amount of expression of the hGH gene in mammary gland of transgenic mice. The amount of hGH was 13.3ng/ml in the lactating milk of one transgenic line, showing predominantly higher than 3.0ng/ml in milk of control mice. Therefore, our findings suggested that $\beta$-casein promoter may induce the tissue specific expression of structural gene.

• Korean Journal of Animal Reproduction
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• v.24 no.4
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• pp.419-428
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• 2000

Leptin, the product of obese (ob) gene, is an adipocyte-derived satiety factor that plays a major role in the regulation of food intake, energy homeostasis, body weight, reproductive physiology and neuropeptide secretion. The present study was designed to generate transgenic mice expressing antisense mouse ob (mob) gene. Total RNA was extracted from the adipose tissues of mouse, then reverse transcription was performed. The 303 and 635 bp fragments of anti I and II cDNAs were amplified from mob cDNAs by PCR. The two mob cDNAs were reversely ligated into between adipose tissue specific aP2 promote and SV40 poly(A) site. Transgenic mice carrying two different kinds of antisense mob transgenes were generated by DNA microinjection into pronucleus. Total 14 transgenic mice were born, and the 4 and 5 founder lines of the transgenic mice with anti I and II transgenes were respectively established. Antisense mRNA expression was detected in transgenic F$_1$ mice by RT-PCR analysis. This result suggests that the transgenic mice expressing antisense mob mRNA may be useful as an animal disease model to be obesity caused by decreased amount of leptin secretion.

• Korean Journal of Animal Reproduction
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• v.14 no.3
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• pp.191-197
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• 1990

The transgenic mice were produced by microinjection of human growth hormone gene fused with mouse metallothionein Ⅰ promoter. They were mated with momal mice by backcross or brother-sister mating. The reproduction efficiencies of female and male n the FO transgenic mice were 17.6%(3/17 mice) and 31.2%(5/16 mice), respectively, and were very lower than that in normal mice(85.7% and 100%, respectively). Interestingly, a few of female transgenic mice were fertile which was different from the previous reports. Of 6 fertile transgenic mice, 2 mice were identified as mosaic type by the reduced frequency of genetic transmission to successive generation below Mendelian levle and the enhanced copy numbers of transgene in progeny mice compared with the transgenic parent. In the group of F1, F2, F3 transgenic mice the reproduction efficiencies of males were gradually improved, whereas females were absolutely infertile. It was consequently shown that the transgenic mice expressing human growth hormone gene were frequently infertile, but the genotypic and phenotypic characteristics of the fertile transgenic mice were normally passed on to the progeny through herm line. Therefore it must be considered wheter or not the products of foreign DNA introduced into animals will detrimentally affect their physiological aspects.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.07a
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• pp.38-38
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• 2005

• 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)

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.57-57
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• 2006