A novel strategy for programmable DNA tile self-assembly with a DNAzyme-mediated DNA cross circuit

As people are placing great importance on controlling the construction process of complex nanostructures, an increasing number of self-assembly strategies have been developed and utilized. Among them, dynamic DNA circuits as a trigger element to control DNA tile assembly have become an area of intense research. However, many significant challenges still exist in terms of improving the modularity and controllability of dynamic DNA circuits and realizing programmable DNA tile self-assembly. In this article, we construct a controllable DNA cross circuit based on a DNAzyme using a new control method and realize a programmable DNA tile self-assembly strategy by integrating a DNA cross circuit and DNA tile self-assembly. The basic idea of this new control method is to bidirectionally control the activity of the DNAzyme by changing the conformation of the DNAzyme, so as to realize the controllability of signal conversion in the DNA cross circuit. Based on this new control method, we design two double-stranded structures. Then, different inputs are used to activate the corresponding DNAzymes to further construct the modular DNA cross circuit. At the same time, the modular DNA cross circuit is used to realize different DNA tile assembly methods. The design of this system provides a new idea for generating dynamic and controllable trigger elements and broadens the programmable range of stimuli-responsive self-assembly. The proposed strategy promotes the controllability and modularization of trigger elements, realizes programmable molecular self-assembly, and has broad applications for the construction of DNA nanodevices.