The wending rhombus: Self-assembling 3D DNA crystals

Abstract

In this perspective, we provide a summary of recent developments in self-assembling three-dimensional (3D) DNA crystals. Starting from the inception of this subfield, we describe the various advancements in structure that have led to an increase in the diversity of macromolecular crystal motifs formed through self-assembly, and we further comment on the future directions of the field, which exploit noncanonical base pairing interactions beyond Watson-Crick. We then survey the current applications of self-assembling 3D DNA crystals in reversibly active nanodevices and materials engineering and provide an outlook on the direction researchers are taking these structures. Finally, we compare 3D DNA crystals with DNA origami and suggest how these distinct subfields might work together to enhance biomolecule structure solution, nanotechnological motifs, and their applications.

Figure 1

DNA motifs that self-assemble into 3D DNA crystals. The top row depicts the schematic design with the single unit structure; the middle row shows the view from atop the lattices; and the bottom row shows the side view of the long-range crystal lattices, with PDB IDs inset. (a) A tensegrity triangle motif self-assembles into a rhombohedron (R3 space group) via sticky-end cohesion (27) (PDB: 3GBI). (b) An unwrapped tensegrity triangle motif with a central five-nucleotide repeating sequence results into a layered structure with P3₂21 symmetry (31,32,33,34) (PDB: 5KEK). (c) A DNA 13-mer self-assembles into the stacked layers of parallel helices connected with parallel-stranded base pairing in P6₄ symmetry (35) (PDB: 1P1Y). (d) Non-Watson-Crick sticky-end interactions result in an alternate, 3D hexagonal arrangement (P6₃ space group) of tensegrity triangles (36) (PDB: 7R96). To see this figure in color, go online.