"Our work shows that we can control the construction of three-dimensional arrays made from RNA blocks of different shapes and sizes," said Peixuan Guo of Purdue. "With further research, RNA could form the superstructures for tomorrow's nanomachines."
To date, much of the research into biological molecules for use in nanotechnology has focused on DNA molecules and proteins. RNA has the advantage of being manipulable into versatile shapes, whereas DNA is largely limited to a double-helical structure.
"RNA combines the advantages of both DNA and proteins and puts them at the nanotechnologist's disposal," said Guo. "It forms versatile structures that are also easy to produce, manipulate and engineer."
Guo and colleagues used pRNA molecules from the DNA-packaging motor of bacterial virus phi29. These molecules form hexameric rings. By tailoring the design of the pRNA, the team was able to induce the molecules to assemble into a variety of new shapes, including twins, tetramers, triangles, rods and three-dimensional arrays.
"By designing sets of matching RNA molecules, we can programme RNA building blocks to bind to each other in precisely defined ways," said Guo. "We can get them to form the nano-shapes we want."
Now the researchers, who reported their work in Nano Letters, are working on ways to make the RNA structures more resistant to degradation over time.