Researchers at HMS have developed new, complex three-dimensional structures they call bricks. Don’t think you’ll be able to build a house with them, though. These bricks are formed from self-assembled DNA strands.
Why use DNA?
“We like DNA because it is simple to design with, easy to program, and produces a robust structure,” says Yonggang Ke, an HMS research fellow in biological chemistry and molecular pharmacology at the Dana-Farber Cancer Institute. Ke has worked on the project for the past two years.
DNA also holds a lot of information, a useful property when you want the molecule to direct itself into forming a desired complex structure. Getting molecules to configure themselves in useful ways is fundamental to the field of DNA structure technology, a form of molecular engineering that Ke pursues.
When the nucleic acids that make up DNA self-assemble into a single-stranded version of the molecule, the information they contain directs them to form what Ke and his colleagues refer to as a brick. Each brick is a modular unit, and like a LEGO block, it can connect to four neighboring bricks to form a module. Each of those four bricks is also capable of linking with neighboring bricks. Complex structures form as the number and position of modules vary. Think of a computer: small parts are assembled into larger components that interact with nearby sections in order to operate. So far in his work, Ke has been able to direct the bricks into more than 100 distinct shapes.
Ke, who works in the laboratory of Peng Yin, an HMS assistant professor of systems biology and a core faculty member of the Wyss Institute for Biologically Inspired Engineering at Harvard, says that although DNA structure technology has been around for 30 years, most of the designs produced by researchers are two-dimensional. But if researchers want to simulate biochemical reactions in cells, Ke says three-dimensional structures would be more useful.
“The most exciting thing for me is realizing this method enables us to make something much more complex than the two-dimensional structures we have,” says Ke.
The technology has applications for biological and biomedical engineering. Ke sees drug delivery, biosensors, and tissue engineering as among the most promising biomedical applications. The bricks offer shape control and site-specific functionality—they can be put anywhere—characteristics that the team suspects will aid future applications.