• 한국환경성돌연변이발암원학회지
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• 제15권2호
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• pp.100-105
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• 1995

The effects of DNA polymerase $\beta$ on the somatic chromosome mutations and mitotic recombinations were investigated using the transgenic Drosophila beating chimetic gene consisting of a promoter region of Drosophila actin 5C gene and rat DNA polymerase $\beta$. For detecting the somatic chromosome mutations and mitotic recombinations, the heterozygous (mwh/+) strains possessing or lacking transgene poi 13 were used. The spontaneous frequency of small mwh spots, due to deletion or nondisjunction etc., in the non-transgenic w strain and the transgenic p[pol $\beta$]-130 strain was 0.351 and 0.606, respectively. The spontaneous frequency (0.063) of large mwh spots, arises mostly from somatic recombination between the centromere and the locus mwh, in the transgenic p[pol $\beta$]-130 strain was about three times higher than that (0.021) of the non-transgenic w strain. The mutant clone frequencies of small and large mwh spots induced by N-methyl-N'-nitro-N-nitrosoguanidine and ethyl methanesulfonate in the transformant p[pol $\beta$]-130 were higher than those in the host strain w. The present results suggest that rat DNA polymerase $\beta$ participate at least in the somatic chromosome mutations and mitotic recombination processes.

• 한국가축번식학회지
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• 제22권2호
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• pp.127-136
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• 1998

A chimeric gene comprising murine whey acidic protein(mWAP) and human growth hormone(hGH) was used to produce transgenic rats express hGH and secrete it into the blood. Two lines of transgenic rats carrying the mWAP/hGH construct were established; High line was characterized by relatively high levels of serum hGH, and low line had relatively low levels. The secretory profiles of rat GH(rGH) as well as hGH, the transgene product, were obtained in transgenic males and females of low line; both hGH and rGH serum levels were flattened with no episodic fluctuations, and the overall mean concentration of rGH was significantly lower than in normal littermates. Although the animals of High line showed an acceles, as assessed by vaginal opening and occurrence of first ovulation, advanced by 7∼8 days in both lines of animals. Accordingly, the body weight at puberty of low line transgenic females was much lower than that of normal littermates, indicating that continuous hGH expression could induce precocious puberty without enhancing the growth rate.

• 한국가축번식학회지
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• 제17권4호
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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.

• 한국가축번식학회지
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• 제22권2호
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• pp.137-143
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• 1998

The effects of continuous GH(hGH) secretion on the female reproduction was studies in adults female transgenic rats expressing the hGH gene with a mouse whey acid protein (mWAP) promotor. Two line of transgenic female rats carrying the mWAP/hGH gene were established and used in the study. One was characterized by relatively high levels of serum hGH (high line), and the other had relatively low levels (low line). 1. High line female rats had recurring, Pseudopregancy-like estrous cycles accompanied by increased serum progesterone level for 2 weeks after ovulation, and they were fertile. 2. In the rats, luteinization occurred spontaneously without cervical stimulation, probably due to high levels of serum hGH, which has prolactin (PRL)-like activity in the rat. 3. Low line female rats had recurring, regular 4-days estrous PRL surge following cervical stimulation were not, detected and PRL secretion was not induced by a dopamine antagonist. 4. The ovarian tissue in this line had a much higher number of corpora lutea and grew much heavier than in normal littermates, suggesting impairment of PRL induced structural luteolized. Su, pp.ession of PRL secretion in the low line rats was, at least in part, due to a marked decrease in the number of lactotrophs in the pituitary. The present study shows that the serum hGH level plays a crucial role in regulating luteal function in female transgenic rats expressing the hGH gene.

• 한국가축번식학회지
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• 제18권2호
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• pp.133-139
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• 1994

Two human lactoferrin expression vectors(pCChcLf and pCChcLf-1) were constructed using rat $\beta$-casein gene and human lactoferrin cDNA. The recombinant DNAs containing human lactoferrin cDNA were microinjected into the fertilized eggs of hybrid mice (BDF1 : C57BL$\times$DBA) and the DNA-injected eggs were treansferred into the oviducts of foster mothers. Genomic DNAs were isolated from the tails of mice born from the microinjected eggs and analyzed by Southern blot analysis. As a result, 5 and 9 transgenic mice with CChcLf and CChcLf-1 gene were produced, respectively. To determine tissue-specificity of transgene expression, Northern blot analysis was performed. Female transgenic mice were killed at day 10 of lactation and total RNAs from various tissues were isolated. Based on Northern blot analysis, it was shown that transgene was mainly expressed in the mammary glands of transgenic mice. In addition, the human lactoferrin in milk was detected by enzyme-linked immunosorbent assay. For this study, milk was obtained from the mammary glands of the transgenic mice at day 10 of lactation. In line #2 of CChcLf and line #7 of CChcLf-1 transgenic mice, human lactoferrin was secreted into the milk at concentration levels of 340ng/ml and 60ng/ml, respectively.

• 한국가축번식학회지
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• 제22권2호
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• pp.145-152
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• 1998

Many trials have been made to produce transgenic animals using sperm cells as a vector transferring foreign DNA into eggs, but reliable results are yet to be obtained (Brinster et al., 1989; Lavitrano et al., 1989; Bachiller et al., 1991; Sato et al., 1994). Recently, one of author(SO) demonstrated that mouse blastocysts derived from eggs fertilized by spermatozoa of male mice single injected with liposome-DNA complexes within the testis expressed thegene (Ogawa et al., 1995.) Here we report that a single injection of liposome-encapsulated DNAs into the testis of either male rats or mice resulted in successfully gene transfer to the postpartum progeny. The expression of mRNA derived from transgenes was also demonstrated in transgenic animals thus obtained. Further, the transmission of the exogenous gene to the descedants was confirmed in one line of transgenic rat up to F4 generation, indicating that the gene was stably incorporated into the germ line. Thus, direct single injection of foreign DNA into the testis provides a novel and convenient means to generate transgenic animals.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2001년도 Korean Environmental Mutagen Society
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• pp.183-183
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• 2001

• 한국독성학회:학술대회논문집
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• 한국독성학회 2005년도 춘계 국제심포지엄 및 학술대회
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• pp.112-112
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• 2005

• 한국응용곤충학회지
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• 제35권4호
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• pp.315-320
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• 1996

Drosophila의 actin 5C 유전자 promoter에 쥐의 DNA polymerase $\beta$cDNA를 도입시킨 형질전환 초파리가 고감수성 환경성 변이원 검출계로 사용할 수 있는지를 조사하였다. 체세포 염색체 재조환과 체세포 염색체 돌연변이의 검출을 위해서는 geterozygous(mwh/+) 계통을 사용하였다. 염색체상의 결실이나 비분리 등에 의한 small mwh spot의 자연 발생적 빈도는 non-transgenic w 계통과 transgenic p[pol $\beta$]-130 계통에서 각각 0.351 및 0.606 정도였다. 체세포 염색체 재조환에 의한 large mwh spot의 자연 발생적 빈도의 경우는 transgenic p[pol $\beta$]-130 계통(0.063)이 non-transgenic w 계통(0.021)에 비해 약 3배 정도 높게 나타났다. IQ, Glu-P-1 및 {TEX}$AFB_{1}${/TEX} 등의 돌연변이원의 처리에 의한 경우, 두 종류의 mutant clone의 발생 빈도는 쥐의 DNA polymerase $\beta$가 도입된 transgenic p[pol $\beta$]-130 계통이 non-transgenic w 계통에 비하여 모두 약 2-3배 정도 높게 나타났다. 본 연구의 결과는 쥐의 DNA polymerase $\beta$가 최소한 체세포 염색체 돌연변이 유발이나 체세포 염색체 재조환의 생성 과정에 관여함을 의미하며, 형질전환 초파리 계통이 환경성 변이원 검출계로서 충분한 응용가능성이 있음을 보여 주었다.

• 한국수정란이식학회지
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• 제27권4호
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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.