DNA nanomachines

Abstract

We are learning to build synthetic molecular machinery from DNA. This research is inspired by biological systems in which individual molecules act, singly and in concert, as specialized machines: our ambition is to create new technologies to perform tasks that are currently beyond our reach. DNA nanomachines are made by self-assembly, using techniques that rely on the sequence-specific interactions that bind complementary oligonucleotides together in a double helix. They can be activated by interactions with specific signalling molecules or by changes in their environment. Devices that change state in response to an external trigger might be used for molecular sensing, intelligent drug delivery or programmable chemical synthesis. Biological molecular motors that carry cargoes within cells have inspired the construction of rudimentary DNA walkers that run along self-assembled tracks. It has even proved possible to create DNA motors that move autonomously, obtaining energy by catalysing the reaction of DNA or RNA fuels.

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Figure 1: Self-assembly of a nanometre-scale object.
Figure 2: A DNA nanomachine driven by repeated sequential addition of DNA control strands.
Figure 3: DNA nanomachines that execute directional stepwise movement along linear tracks.
Figure 4: Hairpin loops to fuel DNA motors81.
Figure 5: Scheme for a hybridization-powered molecular motor.

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Acknowledgements

This work was supported by the UK research councils BBSRC, EPSRC and MRC, and by the MoD through the UK Bionanotechnology IRC.

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Correspondence to Andrew J. Turberfield.

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Bath, J., Turberfield, A. DNA nanomachines. Nature Nanotech 2, 275–284 (2007). https://doi.org/10.1038/nnano.2007.104

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