Integration of a target gene into chromosomal genome of BF-2 cells using UV-inactivated snakehead retrovirus (SnRV)

  • Published : 2009.12.01

Abstract

Integration and expression of a target gene into chromosomal genomes of host cell by retrovirus mediated gene transfer system usually require complicate and laborious procedures. In the present study, we investigate a simple method to integrate a target gene into genome of BF-2 cells using ultraviolet (UV)-inactivated snakehead retrovirus (SnRV), a fish retrovirus. First of all, an optimization of transfection condition was determined with BF-2 cells using Lipofectamine 2000 and Transome. Using 0.5 $\mu\ell$ Lipofectamine 2000 resulted in 33.8, 40.6 and 40.2% of transfection efficacy with high survival rate (minimum 80%) in 0.5, 1 and 2 $\mu{g}$ DNA, respectively, and those of Transome were all less than 5%. It was confirmed that UV-treatment for 5 min was enough to inactivate infectivity of SnRV. Next, a cassette composed of GFP (green fluorescent protein) gene flanked by LTR (long terminal repeats) sequences derived from SnRV was constructed and transfected into BF-2 cells followed by treatment with UV-inactivated SnRV for optimization of integration and expression of the cassette gene. As the results, the fluorescence was expressed in BF-2 cells treated with UV-inactivated SnRV 3 and 5 times, while there was no expression in BF-2 cells with once and non treatment. Accordingly, it was confirmed that GFP gene was integrated into chromosomal genome of BF-2 cells with UV-inactivated SnRV.

목적 유전자를 숙주 세포의 게놈에 삽입하거나 발현하는데 있어서, retrovirus 매개의 유전자 전달 시스템을 사용하게 되면, 복잡하고 힘든 절차를 거치게 된다. 본 연구에서는 목적 유전자의 BF-2 세포 게놈 내 삽입을 하기 위해, UV로 불활화한 어류 레트로바이러스인 SnRV를 사용한 간단한 방법에 대해 조사하였다. 우선, BF-2 세포를 사용한 transfection을 위해 Lipofectamine 2000과 Transome을 사용하여 최적 조건을 결정하였다. 0.5 $\mu\ell$ Lipofectamine 2000을 사용한 경우 0.5, 1 그리고 2 $\mu{g}$ DNA 사용에 대해 33.8, 40.6 그리고 40.2%의 transfection 효율을 보인 동시에 최소 80 % 이상의 높은 세포 생존율을 나타낸 반면, Transome을 사용한 transfection 효율은 모두 5% 이하였다. UV 처리 시간에 있어서는 5분간의 UV 처리로 SnRV의 감염성이 불활성화되는 것을 확인하였다. 다음으로 GFP 유전자의 양측에 SnRV에서 유래된 LTR 서열을 접하고 있는 cassette를 구축한 뒤 BF-2 세포에 transfection 하고, cassette 유전자의 삽입과 발현을 위해 UV로 불활화한 SnRV를 처리하였다. 그 결과 UV로 불활화한 SnRV를 1회 처리 또는 SnRV 무처리 BF-2 세포에서는 형광이 관찰되지 않았던 반면, 3회와 5회 처리한 BF-2 세포에서 형광발현이 확인되었다. 이러한 결과로, GFP 유전자가 불활화한 SnRV를 이용하여 BF-2 세포 게놈에 삽입되는 것을 확인하였다.

Keywords

References

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