DNA Legos: Build Your Own 3D DNA Structures
DNA strands can be broken down into simple bricks and tiles to then construct self-assembling, complex 3D structures.
--by Nina Lincoff
It seems that kids who spend hours playing with Legos will grow up to be…nucleic acid scientists.
not, (though we'd like to think so). Researchers at Harvard and Aarhus
University in Denmark have developed ways to coax single-strands of DNA
into individual tiles and bricks that can then be assembled—or assemble themselves—into 102 complex 3D shapes. Their findings appear on the cover of the latest issue of Science.
These DNA ‘Legos’ offer amazing potential for advancements in nanotechnology and medicine. For example, customized DNA structures could function as nano-scale delivery systems for vaccines or medications.
Nucleic acids are large molecules that, in the most primal sense, contain, transmit, and control the expression of genetic information. The most well known nucleic acids are DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). These contain a blueprint for the shape, function, and development of all life.
The ability to manipulate short, synthetic DNA strands into DNA bricks offers a range of possibilities for both research and medical breakthroughs. A great way to affect change or healing in the body is, of course, to alter its blueprint.
The Expert Take
The 102 distinct DNA shapes are exciting, says lead study author Yonggang Ke, Ph.D., because they demonstrate the properties and potentials of the new DNA-brick technique in making complex, 3D DNA structures. 102 shapes were chosen for two reasons, says Ke—to show the modularity and rapid prototype ability of the DNA-brick technique and to demonstrate how complex shapes that were previously impossible to make can now be synthesized.
Structures with tunnels and complex surface features (think Arabic script as a DNA structure) have never been demonstrated before.
The difference between these structures and those of the past, says Ke, “is that the new SST technique provides a powerful way to rapidly design and construct complex structures that are not accessible before.” Hopefully, Ke's findings will improve the technology's existing applications and attract more researchers to the study of DNA ‘Legos.’
While this development is still largely theoretical, the implications of designing self-assembling 3D DNA structures out of individual 32-nucleotide bricks are incredibly exciting. Potential uses of these bricks include smarter drug delivery particles, electronic applications, and nanostructures with chemical properties designed to slip into something as complex as a living cell or life form.
Source & Method
Each 32-nucleotide DNA strand has four 8-nucleotide sticky ends, which researchers can stick together or pull apart to form 2D or 3D structures. DNA bricks can be utilized as a boundary half brick (exposed at the edges of a structure and cut in half) a protector brick (the buffer at the first or last layer), or some combination of both functions.
Shapes the researchers created ran the gamut from solid shapes with extrusions and different surfaces, to closed-cavity shapes that essentially function as empty boxes with differently shaped cavities, to open-cavity shapes that have a single tunnel in a variety of widths and depths, to multiple-parallel cavities with non-intersecting tunnels, to solid base shapes with features that range from a full set of lowercase letters in the English alphabet to concentric rings.
A secondary portion of this study observed the construction of DNA origami, or the building and folding of complex lattice structures using DNA bricks and tiles. Researchers from the Biodesign Institute at Arizona State University presented a strategy to design self-assembling DNA nanostructures using DNA origami of high-curvature DNA strands.