A synthetic DNA motor that transports nanoparticles along carbon nanotubes

• Published in: Nature nanotechnology Vol. 9; no. 1; pp. 39 - 43
• Main Authors: Cha, Tae-Gon, Pan, Jing, Chen, Haorong, Salgado, Janette, Li, Xiang, Mao, Chengde, Choi, Jong Hyun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.01.2014; Nature Publishing Group
• Subjects: 147/3; 639/925/926/1048; Adenosine triphosphate; Adenosine Triphosphate - chemistry; ATP; Carbon; Deoxyribonucleic acid; DNA; DNA - chemistry; Dyneins - chemistry; Emissions; Energy; Enzymes; Fluorescence; Hydrolysis; Kinesin - chemistry; letter; Materials Science; Microtubules - chemistry; Models, Molecular; Motors; Movements; Nanocrystals; Nanoparticles; Nanoparticles - chemistry; Nanotechnology; Nanotechnology and Microengineering; Nanotubes, Carbon - chemistry; Ribonucleic acids; Translocation; Transport; Velocity; Walking; Indiana; United States > US
• ISSN: 1748-3387; 1748-3395
• DOI: 10.1038/nnano.2013.257

Intracellular protein motors have evolved to perform specific tasks critical to the function of cells such as intracellular trafficking and cell division 1 , 2 . Kinesin and dynein motors, for example, transport cargoes in living cells by walking along microtubules powered by adenosine triphosphate hydrolysis 3 , 4 . These motors can make discrete 8 nm centre-of-mass steps and can travel over 1 µm by changing their conformations during the course of adenosine triphosphate binding, hydrolysis and product release 5 , 6 . Inspired by such biological machines, synthetic analogues have been developed including self-assembled DNA walkers that can make stepwise movements on RNA/DNA substrates 7 , 8 , 9 , 10 , 11 , 12 or can function as programmable assembly lines 13 . Here, we show that motors based on RNA-cleaving DNA enzymes 14 can transport nanoparticle cargoes—CdS nanocrystals in this case—along single-walled carbon nanotubes. Our motors extract chemical energy from RNA molecules decorated on the nanotubes and use that energy to fuel autonomous, processive walking through a series of conformational changes along the one-dimensional track. The walking is controllable and adapts to changes in the local environment, which allows us to remotely direct ‘go’ and ‘stop’ actions. The translocation of individual motors can be visualized in real time using the visible fluorescence of the cargo nanoparticle and the near-infared emission of the carbon-nanotube track. We observed unidirectional movements of the molecular motors over 3 µm with a translocation velocity on the order of 1 nm min −1 under our experimental conditions. Motors based on RNA-cleaving DNA enzymes can transport cadmium sulphide nanocrystals along single-walled carbon nanotubes.