• 한국가금학회지
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• 제26권2호
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• pp.119-129
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• 1999

In recent years, numerous researches have been carried out in author's laboratory to develop several kinds of methods for producing transgened chicken, leaving a lot of new findings. Some of them are very useful to search for new approaches necessary to improve the efficiency of hatchability and the survival rate of developing trasgened embryos. The results obtained hitherto might be summarized as follows: (1) foreign gene(Lac Z/ Miw Z) introduced into blastodermal cells of developing embryos was successfully transferred to embryos, leading to the production of primordial germ cells(PGCs) carrying foreign DNA. However, hatched hickens failed to show the incorporation of introduced gene into the gonads. (2) When foreign gene was introduced into germinal crescent region (GCR), the gene was also efficiently incorporated into germ cells, resulting in the production of transgened chickens(offspring) which produced fruther offspring having foreign gene in the gonads. In this case, 2nd and 3rd generations of chickens were obtained through the reproduction of transgened birds. (3) In another way, the gene was injected into blood vessels of developing embryos at stage 13∼15, creating PGCs having foreign gene, and produced some transgened chickens. In this work, the PGCs were transfered between embryos, resulting in the production of transgenic chickens. (4) in these experiments, PGCs were effectively employed for producing transgenic birds, developing some kinds of chimeric chickens from homo- or hetero-sexual transfer of the PGCs from embryos. This means that the gonads from donor PGCs developed in some degree to the stage of hatching. However, these gonads showed slightly abnormal tissues similar to ovotestis like organs through histological examination. (5) Avian Leukosis Virus(ALV) induced B cell line(DT40) successfully carried foreign genes into chicken embryos, suggesting the possibility of the cells as a vector in this field of study in the future. (6) Inter-embryonic transfer of the PGCs also gave us some.

• Clinical and Experimental Reproductive Medicine
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• 제39권3호
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• pp.95-106
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• 2012

It has been revealed that multiple cohorts of tertiary follicles develop during some animal estrous cycle and the human menstrual cycle. To reach developmental competence, oocytes need the support of somatic cells. During embryogenesis, the primordial germ cells appear, travel to the gonadal rudiments, and form follicles. The female germ cells develop within the somatic cells of the ovary, granulosa cells, and theca cells. How the oocyte and follicle cells support each other has been seriously studied. The latest technologies in genes and proteins and genetic engineering have allowed us to collect a great deal of information about folliculogenesis. For example, a few web pages (http://www.ncbi.nlm. nih.gov; http://mrg.genetics.washington.edu) provide access to databases of genomes, sequences of transcriptomes, and various tools for analyzing and discovering genes important in ovarian development. Formation of the antrum (tertiary follicle) is the final phase of folliculogenesis and the transition from intraovarian to extraovian regulation. This final step coordinates with the hypothalamic-pituitary-ovarian axis. On the other hand, currently, follicle physiology is under intense investigation, as little is known about how to overcome women's ovarian problems or how to develop competent oocytes from in vitro follicle culture or transplantation. In this review, some of the known roles of hormones and some of the genes involved in tertiary follicle growth and the general characteristics of tertiary follicles are summarized. In addition, in vitro culture of tertiary follicles is also discussed as a study model and an assisted reproductive technology model.

• 한국동물학회지
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• 제27권1호
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• pp.13-24
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• 1984

산개구리의 germ plasm 및 축결정 세포질에 미치는 자외선의 영향을 수량적, 시간적으로 조사하였다. 산개구리 난의 식물극을 수정 후 60분경에 1,600 $ergs/mm^2$이상의 자외선을 조사하였을때 40%이상의 시원생식세포의 수가 감소하였으나, 그 이하의 양에서는 전혀 영향이 없었다. 그러나 1,600 $ergs/mm^2$부터는 시원생식세포 수의 감소 정도는 자외선의 양에 비례하였다. 또 신경관 형성에 전혀 영향을 미치지 않으면서 시원생식세포의 형성을 완전히 억제시키는 자외선의 양은 4,800 $ergs/mm^2$이었다. 이에 4,800 $ergs/mm^2$의 자외선을 수정 후 일정한 시간간격으로 조사하여 germ plasm에 미치는 자외선의 영향을 조사하였다. 그 결과 자외선이 조사된 시기가 이를수록 시원생식세포수의 감소가 크며, 수정후 60분부터 차츰 감소율이 줄어 들다가 3분열 이후에는 자외선의 효과가 거의 없음을 관찰하였다. 또한 시원생식세포와 축형성에 미치는 자외선의 영향을 시기적으로 비교한 결과 산개구리난의 축결정이 다른 무미양서류에서와 같이 수정에서 제1분열 사이의 $0.7\\sim0.8$시기 이전에 이루어지므로 그 이후에는 자외선의 감응도가 급격히 저하되었다. 그러나 germ plasm의 자외선에 대한 감응도는 훨씬 늦게까지 지속되어 8구기에 이르기까지 그 영향이 나타났다.

• 한국발생생물학회지:발생과생식
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• 제24권4호
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• pp.249-261
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• 2020

Spermatogonial stem cells (SSCs) have stemness characteristics, including germ cell-specific imprints that allow them to form gametes. Spermatogenesis involves changes in gene expression such as a transition from expression of somatic to germ cell-specific genes, global repression of gene expression, meiotic sex chromosome inactivation, highly condensed packing of the nucleus with protamines, and morphogenesis. These step-by-step processes finally generate spermatozoa that are fertilization competent. Dynamic epigenetic modifications also confer totipotency to germ cells after fertilization. Primordial germ cells (PGCs) in embryos do not enter meiosis, remain in the proliferative stage, and are referred to as gonocytes, before entering quiescence. Gonocytes develop into SSCs at about 6 days after birth in rodents. Although chromatin structural modification by Polycomb is essential for gene silencing in mammals, and epigenetic changes are critical in spermatogenesis, a comprehensive understanding of transcriptional regulation is lacking. Recently, we evaluated the expression profiles of Yin Yang 1 (YY1) and CP2c in the gonads of E14.5 and 12-week-old mice. YY1 localizes at the nucleus and/or cytoplasm at specific stages of spermatogenesis, possibly by interaction with CP2c and YY1-interacting transcription factor. In the present article, we discuss the possible roles of YY1 and CP2c in spermatogenesis and stemness based on our results and a review of the relevant literature.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2000년도 추계학술대회 및 정기총회
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• pp.60-61
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• 2000

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2001년도 발생공학 국제심포지움 및 학술대회 발표자료집
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• pp.47.1-47
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• 2001

One of the problems associated with in vitro culture of primordial gern cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors and antioxidants, on the ability of the porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally, \ulcorner2-macroglobulin, a protease inhibitor and cytokine carrier, and N-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (p<0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layer, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of \ulcorner2-macroglobulin and antioxidatns can increase the number of PGCs in vitro by suppressing apoptosis.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.22-23
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• 2003

Primordial germ cell (PGC) is the progenitor cell of the germ cell lineage and eventually give rise to gametes that are responsible for creating individual organisms via a fertilization process. This means that PGC is a unique cell that can be converted into individual fish. This advantage of PGCs would make it possible to develop various applications in the field of fish bioengineering. First, PGCs may make it easier to preserve the genetic resources of fish. Cryopreservation of fish eggs or embryos has not been successfully achieved so far. Therefore, the only possible method to preserve genetic resources of fishes is to raise fish as live individuals. If PGCs isolated from various fishes could be cryopresewed, these cells could be converted into live fishes via germ-line chimera production. This is particularly useful for preserving genetic materials of endangered species. Even if the species of interest were to become extinct, it could be recovered by the transplantation of cryopreserved PGCs into the embryos of a closely related species. Another application of this technology is in what could be termed "surrogate broodstock technology". (중략)

• Journal of Animal Science and Technology
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• 제55권5호
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• pp.427-434
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• 2013

귀중한 한국재래닭 (오계)의 원시생식세포를 냉동보존하고, 키메라 닭을 통한 재래종의 복원을 도모하는 방법을 실용화하기 위해서, 오계의 원시생식세포에 있어 최적의 동결방법에 대해 검토했다. 원시생식세포의 동결은, 세포를 분리한 후, 동결배지의 기초가 되는 혈청으로서 소 태아혈청 (FBS) 그리고 닭 혈청(CS)를 이용하고, 동결보호제로서는 EG 및 DMSO의 첨가량을 2.5, 5, 10, 15%로 설정하고, 300 ${\mu}L$의 동결배지 용량으로 동결 튜브 안에서 $-70^{\circ}C$로 동결했다. 융해 후에는 오계 PGC의 생존율을 확인 및 검토를 했다. 그 결과, FBS 처리군이 CS 처리군 보다 생존 PGC 회수율이 높은 경향을 나타냈다. 또한 항동해제로서 최적의 조건은 10% EG + FBS의 조합을 기초로 한 동결배지에서 가장 높은 오계원시 생식세포의 생존율을 확인했다. 이러한 결과들로부터 한국재래종(오계)의 원시생식세포의 동결보존의 실용화가 보다 더 향상 될 수 있는 또 하나의 방법이 될 수 있음을 시사한다.

• 한국수산과학회지
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• 제39권3호
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• pp.297-302
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• 2006

황점볼락, Sebastes oblangus의 인공종묘의 성분화 과정 및 성결정을 조사하기 위해 출산 직후부터 370일령까지 조사하였다. 출산 직후 난황기 자어(7.10-7.77 mm)에서 시원생식세 포와 생식융기는 분리된 채 중신관과 장간막 사이에 나타났고, 출산 후 5일령 전기자어(7.12-9.68 mm)에서는 서로 융합하였으며, 출산 후 45일령 후기자어(18.6-20.4 mm)까지는 미분화 생식소 상태였다. 출산 50일 치어(20.0-24.5 mm)에서 생식소 전단부에서 양쪽 끝의 체세포 조직이 분열 신장되어 난소의 분화가 시작되어 60일 치어(25.5-32.0 mm)에서 완전 한 난소강이 형성되었다. 출산 80일령 치어(37.3-47.2 mm)의 난소에서 난원세포가 감수분열을 개시하여 염색인기 난모세포(chromatin nucleolus oocyte) 로 발달하기 시작하였다. 이 후 일령이 증가하여 130일령(68.0-86.0 mm)에서 주변인기(perinucleolus stage)의 난모세포가 나타났으며, 출산 후 370일령(101.0-116.0 mm)에서 전난황형성기의 난모세포들이 출현하였다. 황점볼락 인공종묘의 성비 조사결과 난소분화 완료 후에 암컷만 나타나 출산후 100일까지 자연수온보다 높은 수온에 의해 전암컷화 된 것으로 추정된다.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2005년도 제22차 정기총회 및 학술발표회
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• pp.66-67
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• 2005

배자 생식세포 발달에 관련된 메카니즘을 밝혀내기 위해서, 닭 배자 생식기에서 추출한 원시 생식세포의 단백질체 지도를 만들었다. 총 500 배자를 6일간 배양하여 배자 생식기를 획득했고, 7-10일 배양 후, 배양된 원시생식세포는 2차원 젤 전기 영동법에 의해 분할되어 졌다. 유의적 발현 수준을 나타낸 많은 단백질 스팟 들은 MALDI-TOP 와 LC-MS/MS에 의해 확인되었으며, 89개의 단백질 스팟 중에 50개의 mass spectra 들이 데이터베이스에서 조류 단백질과 일치함을 확인하였다. 본 실험에서 행한 단백질체 지도는 형질전환 연구와 생식세포 생물학 분야에 중요한 참고 문헌으로 가치를 가질수 있을 것이다.