The
competitive endogenous RNA hypothesis is a new mechanism of
RNA dialogue, in which
circRNA-
miRNA interaction (cmRRI) is found to be widely involved in the regulation of gene expression in
tumors and other diseases. It is urgent but challenging to develop a convenient and efficient method to study the interaction between target
circRNA and the candidate
miRNAs. In this work, a biosensing method that allows directly analyzing cmRRI has been developed, so as to reveal the
RNA dialogue strategy. The sensing system uses a bifunctional magnetic bead for the capture of target
circRNA/
miRNA complex as well as the signal amplification. Based on the nature of
circRNA as a
miRNA sponge, only if the target
circRNAs and its regulatory
miRNAs coexist as a complex, can the rolling circle amplification reaction be initiated to give a fluorescent signal as the output. Compared with traditional methods where the
circRNA and its regulatory
miRNAs have been separately analyzed, our design allows the integrated profiling of specific cmRRI by correlation characterization of two correlative RNAs, which represents a function-oriented method. The presented method also shows the analysis of the potential binding affinity of candidate
miRNAs to target
circRNAs. Furthermore, we have verified the ability of the sensor to directly detect cmRRI in biological samples, which reveals the promising applicability of this method for biomedical and clinical researches in the future.