Crisscross DNA Nanotube Growth with Seed-Programmed Diameter and Nucleation-Directed Pathways.

Programmable DNA self-assembly enables nanostructures with custom sizes and architectures from precise DNA origami objects to larger-scale hierarchical assemblies. Crisscross polymerization of DNA slats extends this capability by enabling strictly nucleation-controlled, seed-initiated assembly across length scales, with recent advances demonstrating seed-initiated self-assembly of single-stranded DNA (ssDNA) and DNA origami monomers via joint-neighbor capture. Here, we expand planar crisscross assemblies to develop the seed-directed assembly of crisscross DNA nanotubes. The nanotube diameter could be programmed by the number of nanoseeds arranged within a circular base structure, with each nanoseed nucleating a local growth sector that follows a defined sequence of slat recruitment. Continued nanotube elongation is favored by DNA strand displacement-driven sealing between neighboring growth sectors, which aligns growth fronts to enable efficient subsequent slat capture and accelerate growth. Furthermore, encoding distinct information in the nuc-x-slats enables self-sorting of assembling components from a shared slat library, allowing the same multinanoseed base structure to produce distinct nanotube architectures, including linear nanotubes nucleated by four nanoseeds and split nanotubes nucleated by two nanoseeds. By extension of crisscross polymerization to tubular geometries, this work opens new opportunities for applications in artificial cytoskeletons and algorithmic assemblies.