Molecular DNA devices in Living Systems

Due to its nanoscale dimensions and ability to self-assemble via specific base pairing, DNA is rapidly taking on a new aspect where it is finding use as a construction element for architecture on the nanoscale.1 Structural DNA nanotechnology has yielded architectures of exquisite complexity and functionality in vitro. However, the functionality of such synthetic DNA-based devices in living organisms is yet to be achieved. We have been interested in architecturally simple, yet functional DNA-based molecular devices. Using two examples, from our lab, one of a rigid, DNA polyhedron2,3 and the other a molecular switch4,5 that functions as a pH sensor I will illustrate the potential of DNA based molecular devices as unique tools with which to interrogate living systems. 
Figure 1. Targeted uptake in C. elegans of DNA icosahedra loaded with fluorescent cargo. Image of wild type C. elegans injected (red arrowhead indicates point of injection) with loaded DNA Icosahedra that labels coelomocytes selectively (white arrowheads, scale bar: 100 μm). Inset: Confocal image of a pair of labeled coelomocytes (Scale bar: 10 μm).

References
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