Localized DNA Hybridization Chain Reactions on DNA Origami

The
field of DNA nanoscience has demonstrated many exquisite DNA
nanostructures and intricate DNA nanodevices. However, the operation
of each step of prior demonstrated DNA nanodevices requires the diffusion
of DNA strands, and the speed of these devices is limited by diffusion
kinetics. Here we demonstrate chains of localized DNA hybridization
reactions on the surface of a self-assembled DNA origami rectangle.
The localization design for our DNA nanodevices does not rely on the
diffusion of DNA strands for each step, thus providing faster reaction
kinetics. The locality also provides considerable increased scalability,
since localized components of the devices can be reused in other locations.
A variety of techniques, including atomic force microscopy, total
internal reflection fluorescence, and ensemble fluorescence spectroscopy,
are used to confirm the occurrence of localized DNA hybridization
reactions on the surface of DNA origami. There are many potential
biological applications for our localized DNA nanodevices, and the
localization design is extensible to applications involving DNA nanodevices
operating on other molecular surfaces, such as those of the cell.