• Korean Journal of Animal Reproduction
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• v.18 no.3
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• pp.175-182
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• 1994

Rat $\beta$-casein 유전자와 사람 성장호르몬 (hGH) 유전자의 융합유전자를 생쥐 수정란의 웅성전핵에 미세주입하여 형질전환생쥐 (transgenic mouse) 6계통을 확립하였다. 이들로부터 사람성장호르몬(hGH) 유전자의 발현 여부를 조사한 결과, 6계통중 4계통의 생쥐 유즙에서 hGH가 2~900 ng/ml 수준으로 발현되고 있었으며, 혈중에서는 hGH가 검출되지 않았다. 따라서 이들 형질전환생쥐에서 사람성장호르몬이 우선특이적으로 발현, 분비되고 있음을 알 수 있었다. 한편, 사람성장호르몬의 발현이 확인된 두 계통 (ChGH2-2, CChGH2)의 형질전환생쥐를 대상으로 하여 세대별, 산차별로 유즙내 사람성장호르몬의 함량을 조사한 결과, 3세대에 걸쳐, 또한 제1세대에서의 세차례 반복된 비유기에도 유즙내 사람성장호르몬은 지속적으로 분비되고 있었다. 이상의 결과는 형질전환생쥐에서의 외래유전자의 발현성은 반복되는 비유기와 여러 세대에 걸쳐 안정적으로 유지됨을 보여 주고 있다.

• Korean Journal of Animal Reproduction
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• v.27 no.3
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• pp.225-231
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• 2003

Transgenic mice containing Diphtheria Toxin-A (DT-A) gene fused to proximal lck promoter sequences was used for analysis of DT-A gene expression and thymocyte development. The diphtheria toxin gene was expressed in thymus, spleen and liver of transgenic mice confirmed by RT-PCR and Northern blotting. A FACS analysis with thymocyte cell surface antigens antibodies (CD4 and CD8) showed that the number of peripheral mature single positive thymocytes ($CD4^{+}\;and\;CD8^{+}$ cells) T-cells was severely reduced in transgenic mice compared to that in the non-transgenic littermates. A relative portion of $CD8^{+}$ single positive thymocytes was about 33.2% in transgenic peripheral T-cells while 50.6% in wild type. Reduction of $CD4^{+}$ cell numbers in transgenic mice was observed (5.9% in transgenic versus 10.3% in non-transgenic). The data from analysis of these transgenic mice indicate that the proximal lck promoter regulated the expression of DT-A gene at high level in developing thymocytes and the DT-A disrupted developing thymocytes in transgenic mice.

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.179-185
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• 2003

To determine whether the diphtheria toxin-A (DT) gene disrupts development of thymocytes in transgenic animal, the DT-A gene was used for the production of transgenic mice directed by proximal Ick promoter sequences. Two transgenic founder mice that contained several copies of transgene were produced by DNA microinjection and integration of transgene in transgenic mice was confirmed by PCR and Southern blotting analysis. Transgenic $F_1$ and $F_2$ mice were produced by outbreeding of founder and $F_1$ mice to investigate expression of transgene and phenotypes in transgneic mice. Expression of the diphtheria toxin gene was confirmed in thymus, spleen and liver of transgenic mice by RT-PCR. In circulating blood of transgenic mice, lower number of circulating white blood cells and platelets were observed compared with that of normal mice. In addition, transgneic mice had reduced number of circulating peripheral T-cells analyzed by FACS with anti-CD3 antibody. The data in these transgenic mice indicate that DT gene can play a disruptive role in developing thymocytes of transgenic mice resulted in lower number of T-cells that can be applicable to a wide range of tissues in other animals.

• Korean Journal of Animal Reproduction
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• v.25 no.1
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• pp.85-90
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• 2001

To study the signaling effect of growth hormone (GH) in vivo on animal physiology, transgenic mice containing GH Receptor (GHR) gene fused to metallothionein promoter were produced by DNA microinjection into one-cell stage embryos. Three founder mice were produced with transgenic mice with approximately 4~6 copies of GHR genes and transgene was transmitted into the progeny. The founder mice were mated with normal mice to produce F$_1$ mice, and intergation and transmission of transgene were checked by polymerase chain reaction and Southern blot methods. Transmission rate of GHR transgenic mice were 20~50% in F$_1$ generation and 50% in F$_2$ generation which means that some founder mice were mosaic and transgene in F$_1$ mice was transmitted to F$_2$ progeny with Mendelian ratio. Death rate of GHR transgenic mice after birth was about 10~30% in F$_1$ and F$_2$ progenies indicating that GHR gene may affect death of transgnenic progeny.

• Korean Journal of Animal Reproduction
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• v.27 no.1
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• pp.9-14
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• 2003

The pBT-L transgenic mice carrying human TPO gene in conjunction with bovine $\beta$-casein promoter express human TPO in milk during lactation. In this study, stability of germ line transmission and expression of pBT-L transgene integrated into host chromosome were monitored up to generation F10 of transgenic pBT-L/15 line. When male mouse of generation F8 was crossbred with normal females, approximately half of offsprings (51.3$\pm$18.98%) were identified as transgenic mice. Generation F9 and F 10 mice also showed similar transmission rates (43.8$\pm$18.98% and 71.4$\pm$26.98%, respectively), implying that pBT-L transgene can be transmitted stably up to long term generation in the transgenic mice. Expression levels of human TPO from milk of generation F9 and F10 mice were 1.1$\pm$0.33 mg/ml and 1.1 $\pm$0.45 mg/ml, respectively, which are similar to expression level of generation F2 mice. In conclusion, our results suggest that transgenic animals once established will continuously pass their transgenes to the progeny through the breeding program with the same productivity of human protein in their milk.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.89-89
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• 2003

본 연구에서는 1.7kb 및 3.1kb bovine $\beta$-casein promoter의 유전자 발현 조절능력을 알아보기 위해 1 7kb 및 3.1kb bovine $\beta$-casein promoter에 human Type II Collagen 유전자를 연결해서 DNA microinjection으로 형질전환생쥐를 생산하였다. 총 8마리의 founder생쥐(1.7kb collagen : 5마리, 3.1kb collagen 3마리)를 생산하였고 이 founder생쥐와 wild type 생쥐를 mating시켜서 $F_1 및 F_2$ 새끼를 얻었다. $F_1 및 F_2$새끼들에서 human Type II collagen 유전자의 transmission rate는 약 50%로 Mendel의 법칙에 따라 분리되어 안정적으로 유전자가 염색체에 정착되어 있음을 확인하였다. 이들 $F_1 및 F_2$새끼 중 암컷들을 임신시켜 분만 후 5-10 일경에 유선조직을 포함하여 여러 조직으로부터 RNA를 추출하여 Northern blotting 및 RT-PCR 방법을 이용하여 Type II collagen mRNA의 발현을 분석하였다. 유선에서의 발현은 1 7 kb 및 3.1 kb line별로 각각 1 line씩 발현되지 않았고, 그 외 line에서는 모두 발현되는 것으로 확인되었다. 유선에서의 Type II collagen mRNA 발형양은 1.7 kb 및 3.1 kb bovine $\beta$-casein promoter사이에서는 큰 차이를 나타내지 않았으나 1.7 kb promoter 형질전환생쥐의 경우 유선 이외 조직에서도 발현되는 양상을 나타내었고, 3.1kb promoter line에서는 유선특이적으로 발현시키는 양상을 나타내었다. 그러므로 bovine $\beta$-casein promoter의 1.7 kb와 3.1 kb 사이에 유선특이적 발현을 유도하는 조절부위가 있을 것으로 추정된다.

• 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.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.88-88
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• 2002

Erythropoietin (EPO)는 조혈작용 (erythropoiesis)을 나타내는 호르몬으로서 사람의 빈혈치료제로 사용되며, 포유통물 중 사람, 생쥐 등의 유즙 내에 혈청 EPO 와 동일한 크기로 다량으로 존재한다고 보고된 바 있다. 생쥐의 WAP promoter를 이용하여 사람의 조혈촉진제인 EPO를 유즙으로 생산하는 형질전환돼지 (새롬이)의 유즙을 분석하기 위해 SDS-PAGE와 Western blotting 을 수행하였다. 먼저, 형질전환돼지의 유즙으로부터 원심분리에 의해 지방층을 제거한 후, 16.5% polyacrylamide gel 에서 PAGE를 수행하였다. (중략)

• Development and Reproduction
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• v.6 no.1
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• pp.31-35
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• 2002

The major urinary proteins(MUPs) of mice that bind hydrophobic molecules known as pheromones are regulated in part by the actions of growth hormone. The expression of the MUPs was therefore investigated in transgenic mice that express a human growth hormone-releasing factor gene from a metallothionein gene promoter(MT-GRF) and as a result have elevated growth hormone levels. MUPs were severely down-regulated in the urine of these animals compared to normal mice or to control transgenic mice expressing another gene(the inhibin a subunit) from the same metallothionein promoter(MT-Inh) and more MUPs disappeared in male mice than female ones. MUPs were also down-regulated in the urine of the UT-GRF-injected mice. In addition, it was observed that the urine of the MT-GRF mice included a high molecular weight protein that co-migrates with the major serum protein albumin, indicating an impairment in glomerular filtration within the kidney. The urinary loss of serum proteins was more severe in male MT-GRF mice than female ones. Thus the overexpression of human GRF mimics changes observed in MUP protein expression and glomerular function in other models of growth hormone hypersecretion with sex-dependent differential effects.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.89-89
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• 2003