Construction of DNA Circuit Based on Toehold-mediated DNAzyme Cleavage

As a special type of DNA molecules with molecular manipulation capabilities, DNAzymes possess the abilities of both information storage and information processing. In particular, the integrated application of DNAzymes and DNA strand displacement has enriched the toolbox for the realization of biochemical reactions in biocomputing and provided new methods for constructing diverse and functional DNA circuits. In this paper, we propose a new method for construction of DNA circuit based on toehold-mediated DNAzyme cleavage. In this method, DNAzyme displacement can be triggered through toehold mediation, and then DNAzyme slide along the predesigned track formed by double stranded DNA to achieve the purpose of specific cleavage. Based on this new method, an XOR gate and an INHIBIT gate were constructed firstly, and then a combinatorial DNA circuit, an OR-INHIBIT circuit, was presented. The method of toehold-mediated DNAzyme cleavage provides a flexible and reliable strategy for the construction of DNA circuits and can be applied in the fields such as biological computing, molecular sensing, and DNA nanostructures.