In the fifty-year history since the structure of DNA was first revealed, what was once a Nobel prize- winning research discovery has become an omnipresent cultural icon co-opted for promoting everything from fragrances to musical acts. Now, the familiar DNA double helix is serving as a microscopic trellis in order to further advances in nanotechnology aimed at improving human health.
Hao Yan, a researcher at the Biodesign Institute at Arizona State University and an assistant professor in ASU's Department of Chemistry and Biochemistry, recently created unique arrays of proteins tethered onto self-assembled DNA nanostructures.
While other efforts in recent years have focused on learning how to build DNA-based nanostructures, Yan's work is novel because it makes it feasible to attach any desired biomolecule onto DNA nanostructures. Such work is an important step and can serve as a future foundation for biocatalytic networks, drug discovery or ultrasensitive detection systems.
"Rationally-designed DNA nanoscale architectural motifs have for a long time been envisioned as scaffolds for directing the assembly of biomolecules such as proteins into a functional network," said Yan. "However, the methods to control such assemblies are still scarce. A robust and modular approach is needed. "
In his results, Yan and fellow institute researchers Yan Liu, Chenxiang Lin, and Hanying Li have taken advantage of the base pairing properties of DNA to make the DNA nanostructures. By controlling the exact position and location of the chemical bases within a synthetic replica of DNA, Yan could potentially fashion a variety of DNA assemblies.
In this case, Yan created a triple crossover DNA tile, consisting of three side-by-side helices just six nanometers in width and 17 nanometers in length. One nanometer is one-billionth of a meter. By programming into the assembly a short sequence of DNA that recognizes a particular protein, called an aptamer, Yan created a DNA molecule that could now function as a biomolecular tether.
"This is the first time ever an aptamer has been utilized to link proteins to self-assembled DNA nanoarrays," said Yan.