Three-dimensional structures self-assembled from DNA bricks.

Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA.
Science (Impact Factor: 31.48). 11/2012; 338(6111):1177-83. DOI: 10.1126/science.1227268
Source: PubMed

ABSTRACT We describe a simple and robust method to construct complex three-dimensional (3D) structures by using short synthetic DNA strands that we call "DNA bricks." In one-step annealing reactions, bricks with hundreds of distinct sequences self-assemble into prescribed 3D shapes. Each 32-nucleotide brick is a modular component; it binds to four local neighbors and can be removed or added independently. Each 8-base pair interaction between bricks defines a voxel with dimensions of 2.5 by 2.5 by 2.7 nanometers, and a master brick collection defines a "molecular canvas" with dimensions of 10 by 10 by 10 voxels. By selecting subsets of bricks from this canvas, we constructed a panel of 102 distinct shapes exhibiting sophisticated surface features, as well as intricate interior cavities and tunnels.

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