Programmed Two-Dimensional Self-Assembly of Multiple DNA Origami Jigsaw Pieces

We demonstrate a novel strategy of self-assembly to scale up origami structures in two- dimensional (2D) space using multiple origami structures, named "2D DNA jigsaw pieces", with a specially designed shape. For execution of 2D self-assembly along the helical axis (horizontal direction), sequence-programmed tenon and mortise were introduced to promote selective connections via pi-stacking interaction, sequence-complementarity, and shape-complementarity. For 2D self-assembly along the helical side (vertical direction), the jigsaw shape-complementarity in the top and bottom edges and the sequence-complementarity Of single?: stranded overhangs were used. We designed and prepared nine different jigsaw pieces and tried to,obtain a 3 X. 3 assembly. The proof of concept was obtained by performing the assembly in four different ways. Among them, the stepwise self assembly from the three vertical trimer assemblies gave the target 2D assembly with similar to 35% yield. Finally, the surfaces of jigsaw pieces were decorated with hairpin DNAs to display the letters of the alphabet;, and the self-assembled 2D structure displayed the word "DNA JIG SAW" in nanoscale. The method can be expanded to create self-assembled modules carrying various functional molecules for practical applications.