We have developed an artificial dual promoter cassette system called APRICOT-1-2-3, in which a target gene specific sequence is inserted between inverted two short artificial promoters. A single step PCR protocol has been developed by using this system that allows the production of this cassette in a high throughput manner. Actually, easily prepared APRICOT-1-2-3 constructs induced effective protein expression-silencing for p38MAPK and JNK. The flexibility of this unique design system suggests that additional modification can also easily be introduced into this siRNA expression cassette to improve the convenience applying RNAi.