• 한국가금학회지
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• 제32권4호
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• pp.225-229
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• 2005

현재 가장 활발하게 진행되고 있는 형질전환 자 생산 연구방법은 배반엽단계 수정란에 농축한 virus를 주입하여 모자이크 형태의 $G_0$ 형질 전환체를 생산하고 이들을 이용하여 $G_1$ 형질전환 후대를 생산하는 방법이 가장 보편적으로 이용되고 있다. 상기의 연구방법은 완전한 형질 전환체를 획득하기 위해서는 수천수의 $G_1$을 생산하고 각각 유전분석을 수행하는 문제점을 가지고 있다. 이러한 문제점을 개선하고자 다음의 연구를 계획하고 수행하였다. 20nL의 농축된 GFP retrovirus를 1세포기 수정란에 주입하고, 주입한 유전자의 발현율과 수정란의 생존율을 배양 4일차 수정란에서 GFP의 발현과 배자의 생존 여부로 판정하였다. 연구결과는 배양 4일차 수정란의 생존율은 기존의 naked DNA 미세주입방법에 비해 다소 낮은 것으로 나타났으나 유의성은 없었다. 1세포기 수정란은 배반엽 단계 수정란과 달리 주입한virus의 유전자를 발현하지 않는 것으로 관찰되었다. 연구결과는 배반엽단계 수정란에 virus 미세주입 방법이 형질전환 닭 생산에 가장 효율적인 방법임 보여주고 있다.

• 한국가금학회지
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• 제28권2호
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• pp.125-133
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• 2001

The goal of this paper was to examine the qualify zygote-acquiring method for in-vitro culture and the in-vitro culture method of the acquired zygote from a technological perspective. We have reported the results on the introduction of foreign DNAs using the described culturing method. After performing in-vitro and surrogate eggshell culture on a zygote acquired from the abdomen of a hen, 25.8% hatchability was acquired. After microinjecting foreign DNAs into the acquired zygote and performing in-vitro and surrogate eggshell culture using the same method, 13.1∼11.7% hatchability was acquired. Having compared the developments of the control subjects and the experimental subjects, the viability of the experimental subjects on the 4∼5th day of culturing was much lower compared to that of the control subjects. This is a result that shows that the microinjection process of foreign DNAs might have a negative effect on the existence of the embryo; therefore, various technical attempts should be made to minimize such negative effects. Having microinjected foreign DNAs into the zygote of a hen to produce transgenic chickens, 3 transgenic founders were Produced and 70 G1 progeny were produced as a result of the progeny test that had been performed to the present.

• Asian-Australasian Journal of Animal Sciences
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• 제21권6호
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• pp.801-806
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• 2008

A classical technique to study somitic cell fate is to employ the cross-transplantation of quail somites into a chick host. The densely stained nucleoli of the quail cells makes it possible to assess the fate of the donor quail cells in the chick host. Classical somite transplantation techniques have been hampered by the necessity of a small opening in the chick eggshell, difficulty in hatching the offspring and interspecies post-hatch graft rejection. With the advent of transgenic chicken technology, it is now possible to use embryos from transgenic chickens expressing reporter genes in somite cross-transplantation techniques to remove any possibility of interspecies graft rejection. This report describes using a surrogate eggshell system in conjunction with transgenic chick:chick somitic cell cross-transplantation to generate viable chimeric embryos and offspring. Greater than 40% of manipulated embryos survive past 10 days of incubation, and ~80% of embryos successfully cultured past 10 days of incubation hatched to produce viable offspring.

• 한국가금학회지
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• 제31권4호
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• pp.293-298
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• 2004

본 연구는 기존의 형질전환 닭 생산방법 중의 하나인 1세 포기 수정란에 유전자를 직접 주입하는 유전자 미세주입방법을 개선할 목적으로 리포좀과 외래 표지 발현유전자인 GFP를 사용하여 외래유전자의 핵전이 효율성과 주입된 외래 유전자의 발현의 지속성을 닭의 배자에서 검증하고자 시도하였다 외래유전자는 배반엽 단계 혹은 1세포기 수정란의 세포질에 리포좀과 유전자의 혼합물 혹은 오직 유전자만을 미세주입을 하였다. 연구 결과들은 리포좀을 사용한 경우 naked DNA에 비하여 배반엽 단계와 1세포기 수정란 모두에서 효율적으로 외래 유전자를 핵내로 도입할 수 있음을 배양 3과 4일차 닭의 배자에서 GFP발현 양상을 통하여 확인하였다. 또한 주입된 외래 유전자에 의해 만들어진 GFP는 배자에서 일주일 정도 지속적으로 발현됨이 관찰되었다. 리포좀 방법은naked유전자 주입 방법에 비해 1세포기와 배반엽 단계 수정란 모두에서 효율적으로 외래 유전자를 핵내로 이동시키는 능력을 가지나, 주입된 유전자의 염색체 삽입에는 큰 영향을 미치지 않는 것으로 판단된다. 따라서 닭의 수정란에서 리포좀 방법은 외래유전자 도입에 유용한 수단으로 이용되어질 수 있을 것으로 사료된다.

• 한국발생생물학회지:발생과생식
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• 제11권3호
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• pp.219-226
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• 2007

본 연구는 생식선 키메라 생산효율을 높이기 위한 방법으로 busulfan 가온 주입법을 이용하여 효과적인 원시생식 세포의 이동능력을 검증하였다. 효율적인 생식선 키메라 닭 생산에서 중요한 요건 중 하나인 공여체 원시생식세포의 생존율을 측정한 실험에서는 시간이 지남에 따라 생존율에 변화를 보였으나, 평균 $70{\sim}80%$을 유지하고 있었으며, busulfan 처리 유무에 따른 공여체 원시생식세포 이동능력은 형광염색 후 주입한 실험에서 대조구가 4.8%인 반면 실험구는 23.5%을 나타냈다. 이식전 원시생식세포 배양 조건에 따라, 96시간과 118시간 배양 처리구에서 높은 이동능력을 보여 주었다. 원시생식세포의 형태학적, 생리학적 특징을 응용한 이식방법은 매우 효과적일 것이다. 그리고 본 연구에서는 생식반월의 발달단계 별 busulfan 처리 효과는 48시간이 가장 높은 53.4%였으며, 그러나 본 연구에서는 생식반월 유래 원시생식세포 이식은 48시간 이전, 혈관계가 발달하기 직전으로 가장 높은 효율을 보였다. 결론적으로 생식선 키메라 방법을 통한 형질전환 닭 생산 연구의 가장 큰 관건은 최대한 많은 수의 공여체 원시생식세포가 수용체의 저해작용 없이 안정적으로 수용체 gonad로 이동하여 분화하는 것으로, 본 연구 결과를 토대로 개선된 방법을 이용하면 높은 효율의 생식선 키메라 닭이 생산될 것으로 사료된다.

• Animal Bioscience
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• 제34권8호
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• pp.1321-1330
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• 2021

Objective: Transgenic hens hold a great promise to produce various valuable proteins. Through virus transduction into stage X embryo, the transgene expression under the control of constructed chicken ovalbumin promoters has been successfully achieved. However, a validation system that can evaluate differently developed ovalbumin promoters in in vitro, remains to be developed. Methods: In the present study, chicken oviduct epithelial cells (cOECs) were isolated from oviduct tissue and shortly cultured with keratinocyte complete medium supplemented with chicken serum. The isolated cells were characterized with immunofluorescence, western blot, and flow cytometry using oviduct-specific marker. Chicken mutated ovalbumin promoter (Mut-4.4-kb-pOV) was validated in these cells using luciferase reporter analysis. Results: The isolated cOECs revealed that the oviduct-specific marker, ovalbumin protein, was clearly detected by immunofluorescence, western blot, and flow cytometry analysis revealed that approximately 79.40% of the cells contained this protein. Also, luciferase reporter analysis showed that the constructed Mut-4.4-kb-pOV exhibited 7.1-fold (p<0.001) higher activity in the cOECs. Conclusion: Collectively, these results demonstrate the efficient isolation and characterization of cOECs and validate the activity of the constructed ovalbumin promoter in the cultured cOECs. The in vitro validation of the recombinant promoter activity in cOECs can facilitate the production of efficient transgenic chickens for potential use as bioreactors.

• Asian-Australasian Journal of Animal Sciences
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• 제8권6호
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• pp.557-562
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• 1995

In this study, characteristics of chick primordial germ cells (PGCs), which is the founder cell of the germline, and gonadal development of the chick embryo between 12hrs and 6 day of incubation were investigated by transverse serial sections of chick embryos under the light microscopic observation. In embryo stage 20 (3 day of incubation), there are a lot of PGCs at the mesenchym, which were moving to the thickened epithelium (gonadal ridge). The PGCs arrive at both right and left gonad primordial in equal number prior to stage 24 (4 day of incubation), but in the following stages, the distribution of the PGCs became asymmetrical. More PGCs colonized the left than the right gonad, but the reason for the unequal distribution of PGCs is uncertain. The PGCs have mostly settled in the gonadal ridge (GR) at 6 day embryo. This study was conducted to investigate characteristics of the PGC migration and gonadal formation and observe the best condition for PGC isolation, culture and to attempt the possibility of the production for transgenic germline chimeras with manipulated PGCs.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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• pp.145-145
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• 2005

• 한국가금학회지
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• 제28권2호
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• pp.155-163
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• 2001

Gene and cell transfer technique will serve as a powerful tool for the genetic improvement of the poultry and to yield useful products. For avian transgenesis, Japanese quail may serve as an excellent animal model because of its small body size and fast growth rate. Recent progress was described on the manipulation of quail embryos such as the introduction of foreign genes and cells, and the subsequent culturing of the manipulated embryos yielding hatchlings. Intraspecific donor-derived offspring have been available in quail, however, further investigation will be required to obtain interspecific offspring with the aim of rescuing endangered species. Trans genesis will also be useful for improving the profitability and quality of poultry stocks and for developing stocks with novel uses. Considerable progress should soon be made toward the production of transgenic poultry. The key feature of the procedure described here is that embryos are initially taken out from the shell for ease of manipulation and then placed back in culture in addition to various operations midway during culture.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.163-169
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• 2001

Despite the high potency of the retrovirus vector system in gene transfer, one of the main drawbacks of has been difficulty in preparing highly concentrated virus stock. Numerous efforts to boost the virus titer have ended in unsatisfactory results mainly due to fragile property of retrovirus envelope protein. In this study, to overcome this problem, we constructed our own retrovirus vector system producing vector viruses encapsulated with VSV-G (vesicular stomatitis virus G glycoprotein). Concentration process of the virus stock by ultracentrifuge did not sacrifice the virus infectivity, resulting in more than 108 to 109 CFU (colony forming unit) per ml on most of the target cell lines tested. Application of this high-titer retrovirus vector system was tested on chicken embryos. Injection of virus stock beneath the blastoderms of pre-incubated fertilized eggs resulted in chick embryos expressing E. coli LacZ gene with 100% efficiency. Therefore, our results suggest that it is possible to transfer the foreign gene into chicken embryo using our high-titer retrovirus vector.