Highly Symmetric, Self-Assembling 3D DNA Crystals with Cubic and Trigonal Lattices

Area of Science:

• Nanotechnology
• Materials Science
• Biochemistry

Background:

• Nanoscopic DNA tiles enable self-assembly of highly ordered 2D and 3D crystalline matter.
• DNA tensegrity triangles are well-studied 3D DNA tiles that self-assemble into macroscopic crystals.
• Current 3D DNA crystal design typically uses integer helical turns and Watson-Crick base pairs.

Purpose of the Study:

• To investigate the self-assembly of 3D DNA crystals using unconventional 24-base pair edges in a tensegrity triangle motif.
• To explore the impact of noncanonical base pairs on the resulting crystal symmetry and structure.
• To expand the rational design toolbox for DNA nanotechnology.

Main Methods:

• Substitution of 24-base pair edges into a 21-base pair DNA tensegrity triangle motif.
• Utilizing noncanonical base pairs in sticky ends for self-assembly.
• Comparing results with motifs using Watson-Crick pairs.

Main Results:

• Noncanonical base pairs yielded a cubic arrangement of tensegrity triangles with high symmetry, featuring winding helical axes and diamond-like tessellations.
• Reverting to Watson-Crick pairs resulted in a trigonal hexagonal arrangement, mirroring the diamond pattern in a hexagonal context.
• Demonstrated generation of complex, unexpected pathways for materials design through modification of 3D DNA tiles.

Conclusions:

• Modifying DNA tile design parameters, such as edge length and base pairing, can lead to novel and complex crystalline structures.
• This study expands the possibilities for rational design in DNA nanotechnology.
• Unforeseen crystalline soft matter arrangements can be discovered by exploring unconventional design strategies.