An RNase H-powered DNA walking machine for sensitive detection of RNase H and the screening of related inhibitors
Ribonuclease H （RNase H）, an intracellular ribonuclease, plays a crucial role in cellular processes, and especially relates with many diseases processes. Here, we report a novel signal amplification strategy based on an RNase H-powered DNA walking machine for specific and sensitive RNase H activity detection. The DNA walking machine is composed of a small quantity DNA walker strands and abundant FAM-labeled DNA-RNA chimeric strands on a single gold nanoparticle (AuNP). In the presence of the RNase H, the RNase H can specifically degrade the RNA fragment in DNA-RNA hybrid duplex and trigger the autonomous movement of DNA walker strand on the AuNP surface. During this process, each step of the walking can release the FAM-labeled RNA from the surface of AuNP, realizing the signal amplification for RNase H sensing. This method has been successfully utilized for the RNase H activity detection in the complex system and applied for the screening of related inhibitors. Therefore, our RNase H-powered DNA walking machine gives a novel platform for the RNase H activity detection and the RNase H-associated drug discovery.