Design and Synthesis of Pleated DNA Origami Nanotubes with Adjustable Diameters

ABSTRACT DNA origami allows for the synthesis of nanoscale structures and machines with nanometre precision and high yields. Tubular DNA origami nanostructures are particularly useful because their geometry facilitates a variety of applications including nanoparticle encapsulation, the construction of artificial membrane pores and as structural scaffolds that can spatially arrange nanoparticles in circular, linear and helical arrays. Here we report a simple computational approach that determines minimally-strained DNA staple crossover locations for arbitrary nanotube internal angles. We apply the method in the design and synthesis of radially symmetric DNA origami nanotubes with arbitrary diameters and DNA helix stoichiometries. These include regular nanotubes where the wall of the structure is composed of a single layer of DNA helices, as well as those with a thicker pleated wall structure that have a greater rigidity and allow for continuously adjustable diameters and distances between parallel helices. We also introduce a DNA origami staple strand routing that incorporates both antiparallel and parallel crossovers and demonstrate its application to further rigidify pleated DNA nanotubes.