A novel method to investigate ribonuclease activity of Dicer by square wave voltammetry

Dicer cleaves long double strand RNA (dsRNA) into short ones and initiates RNA interference (RNAi), a sequence-specific post-transcriptional gene silencing process. Moreover, it is also involved in the development of cancers. Herein, we report an electrochemical method to study the ribonuclease activity of Dicer for the first time. The designed dsRNA which is thiolated at one end is firstly immobilized on a gold electrode. Square wave voltammetry is then employed to characterize the ribonuclease activity of Dicer after the enzyme digestion of the dsRNA and the subsequent hybridization between short denatured RNA on the electrode and DNA molecules labeled with electrochemical species. This proposed method shows desirable sensitivity and reproducibility, demonstrating the great potential utility for functional studies of Dicer and RNAi in the future.