Intracellular build-up RNAi with single-strand circular RNAs as siRNA precursors.

We herein report a new approach for RNA interference, so-called "build-up RNAi" approach, where single-strand circular RNAs with a photocleavable unit or disulfide moiety were used as siRNA precursors. The advantages of using these circular RNA formats for RNAi were presented in aspects of immunogenicity and cellular uptake.