An effective method for selecting siRNA target sequences in mammalian cells.

RNA interference is a gene-silencing phenomenon triggered by dsRNA (double-stranded RNA) and has been widely used for studying gene functions. The short interfering RNA (siRNA) responsible for RNA interference, however, varies markedly in its gene-silencing efficacy. Because this efficacy depends on the selected target sequences, we developed an effective selection method based on the gene degradation measure (priority score) defined by positional features of individual nucleotides. We tested this method experimentally by using it to select new siRNA target sequences in the homo sapiens cyclin B1 gene (CCNB1) and confirmed that it selected highly effective gene-silencing sequences. The proposed method will therefore be useful for selecting new siRNA target sequences in mammalian cells.