Establishment of Cell Line with the FEN-1 Gene Blocked by Its Antisense.

FEN-1 is a structure-specific endo/exonuclease, which is involved in the process of both DNA duplication and DNA repair. In this work a mammalian expression vector expressing antisense FEN-1 gene fragment pMAMneoAmp(-)FNB(-) was constructed, after cloning the NcoI-BamHI fragment of FEN-1 gene into the mammalian expression vector pMAMneoAmp(-) in antisense orientation. After FL cell was transfected with pMAMneoAmp(-)FNB(-) and selected by G418, the FL-FEN-1(-) cell line, in which the FEN-1 gene expression was blocked, was established.

The Influence of FEN-1 Gene on Cell Cycle and Genetic Stability.

FEN-1 is essential in the cell replication, repair and in the maintenance of cellular genetic stability. In this report, it was verfied that FEN-1 antisense mRNA fragment was expressed in the cell line FL-FEN-1(-),constructed in our lab, blocking FEN-1 gene expression. It was found by the flow cytometer analysis that the cell cycle of FL-FEN-1(-) cells was delayed in the S-phase DNA synthesis process and arrested in G(1) phase.