OBJECTIVETo silence the expression of Raf-1 gene in HNE1 cells using vector-based RNA interference (RNAi) technique.

METHODSThe vector containing the human U6 promoter was used for targeted gene silencing when a dsDNA oligonucleotide encoding an appropriate shRNA was ligated into the vector, and 67nt oligonucleotide fragment was inserted into the downstream of the U6 promoter. Plasmids containing different Raf-1 target sequences [ (1) pshuttle-Raf-1-a( 225), (2) pshattle-Raf-1-b ( 358) and (3) pshuttle-Raf-1-c(474)], were transfected into HNE1 cells. Expression of Raf-1 mRNA was assayed by RT-PCR. Apoptosis were determined by cytometry.

RESULTSVector-based RNAi had advantages over antisense RNA because it could be delivered to the target cell more efficiently, and effect could last longer. Raf-1 expression could be inhibited by plasmid-expressed shRNA. Three different targeting sequences were selected from Raf-1 gene, and the inhibitory effect of pSIREN shuttle-Raf-1-b (358) was biggest.

CONCLUSIONRaf-1 expression in HNE1 cells can be inhibited significantly using plasmid-based RNAi.