DNAzyme-Controlled Cleavage of Dimer and Trimer Origami Tiles

Dimers of origami tiles are bridged by the Pb²⁺-dependent DNAzyme sequence and its substrate or by the histidine-dependent DNAzyme sequence and its substrate to yield the dimers T₁-T₂ and T₃-T₄, respectively. The dimers are cleaved to monomer tiles in the presence of Pb²⁺-ions or histidine as triggers. Similarly, trimers of origami tiles are constructed by bridging the tiles with the Pb²⁺-ion-dependent DNAzyme sequence and the histidine-dependent DNAzyme sequence and their substrates yielding the trimer T₁-T₅-T₄. In the presence of Pb²⁺-ions and/or histidine as triggers, the programmed cleavage of trimer proceeds. Using Pb²⁺ or histidine as trigger cleaves the trimer to yield T₅-T₄ and T₁ or the dimer T₁-T₅ and T₄, respectively. In the presence of Pb²⁺-ions and histidine as triggers, the cleavage products are the monomer tiles T₁, T₅, and T₄. The different cleavage products are identified by labeling the tiles with 0, 1, or 2 streptavidin labels and AFM imaging.