수핵란의 활성화 시간에 따른 소 체세포 핵이식란의 발육

국문 초록 (Abstract)

본 연구는 융합 전 수핵란의 활성화 처리 유무와 활성화 처리 시간이 소 체세포 유래 핵이식란의 체외 발육능에 미치는 영향을 검토하기 위해 수행하였다. 소 체외성숙란의 탈핵 후 체세포 핵을 이식하고 일부는 전기 융합 후 활성화를 유기하였고(pre-AC), 일부는 먼저 활성화 처리 후 융합을 실시(post-AC)하였다. 난자의 활성화는 Ca2+-ionophore(A23187)로 처리 후 DMAP로 4시간 배양하는 방법으로 유기하였다. 핵이식란은 CR1aa액에서 9일간 배양하여 발육율을 검토하였으며, 활성화 후 30분～2.5시간에 고정하여 confocal microscope 하에서 핵형 변화를 검사하였다. 배반포기까지 발육율은 post-AC구(20.6%)가 pre-AC(15.3%)보다 다소 높게 나타났다. 또한 활성화 처리를 하여 핵이식란의 배 발달을 비교한 결과 post-AC구가 더 늦은 배 발달 속도를 나타내었다. Post-AC구를 활성화 후 30분, 2시간, 4시간으로 나누어 융합하여 발육율을 검토한 결과 발육율에 차이가 없었다. 본 연구의 결과는 수핵란의 활성화 시간에 따라 핵이식란의 발육 및 핵형이 영향을 받을 수 있음을 시사한다.

다국어 초록 (Multilingual Abstract)

This study was conducted to examine the effects of pre activation treatment and activation time of recipient cytoplasm on the development of bovine somatic cell nuclear transfer(NT) embryos. Donor cells were transferred and electrofused to enucleated oocytes before(pre-AC) or after activation(post-AC). Activation was induced with a combination of Ca2+-ionophore(A23187) and DMAP. NT embryos were cultured in CR1aa containing 3 mg/ml BSA for 9 days. Some NT embryos were fixed at 0.5 to 2.5 hr after fusion(for post-AC) or activation(for pre-AC) for confocal microscopy. Developmental rate to the blastocyst stage was slightly high in the post-AC group(20.6%) compared to that of pre-AC group(15.3%). However, developmental speed of embryos in the pre-AC group was faster than that of embryos in the post-AC group. Development rates to the blastocyst stage were similar among different activation time before fusion(0.5, 2 and 4 hr). The result of the present study suggests that development and nuclear morphology are affected by the activation status of the recipient cytoplasm before fusion.

목차 (Table of Contents)

• ABSTRACT
• 요약
• 서론
• 재료 및 방법
• 결과
• 고찰
• 인용문헌

참고문헌 (Reference)

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