Wireframe DNA Origami Capable of Vertex-protruding Transformation

Regulating dynamic behavior of the designed molecular structures provides a foundation for the construction of functional molecular devices. DNA nanotechnology allows conformational changes in two-dimensional and three-dimensional DNA origami nanostructures by introducing flexibility between the faces of the structures. However, dynamic transformations in wireframe DNA origami, composed solely of vertices and edges, remain challenging due to vertex-specific flexibility. We report a wireframe DNA origami capable of vertex-protruding transformation from the open- to the closed-form with eight protruding vertices; this transformation is driven by the hybridization of the signal strands with the zipper strands extending from the edges, leading to structural reorganization. Spacer strands between vertices and edges were designed to introduce flexibility. Coarse-grained molecular dynamics simulations demonstrated that a longer spacer increases conformational flexibility and can achieve the narrow angles required for the vertex-protruding transformation. The experimental results showed the successful assembly of the open-form structure under optimized salt conditions, as visualized through transmission electron microscopy images. Furthermore, the transformation from the open-form to the closed- form was demonstrated by adding signal strands, resulting in designed vertex protrusions. This vertex-protruding transformation mechanism will expand the design approach of dynamic DNA nanostructures and help develop functional molecular devices for artificial molecular systems.