RNA interference (RNA(i)) induction with various types of synthetic oligonucleotide duplexes in cultured human cells.

Various types of synthetic oligonucleotide duplexes against the Photinus luciferase gene were tested on their induction of the sequence-specific RNA interference (RNAi) activity in transfected human cells. Results indicate that RNA duplexes with ribonucleotide 3' overhangs rather than those with deoxyribonucleotide 3' overhangs induce more efficient RNAi activity, and that sense-stranded DNA/antisense-stranded RNA hybrids induce a moderate RNAi activity. These results suggest that there is a difference in the potential of oligonucleotide duplexes to be RNAi mediators, i.e. short interfering RNAs (siRNAs), between human RNAi and invertebrate RNAi. The data further show that different siRNAs induce different levels of RNAi.