Coherent Activation of DNA Tweezers: A 'SET-RESET' Logic System

摘要

Recent research efforts have used the information encoded in base sequences in nucleic acids to develop functional biomolecules that perform mechanical functions, called "DNA machines". Among the DNA structures that perform mechanical functions, nucleic acid tweezers, walkers, molecular gears, and scissors have been reported, and the use of such "DNA machines" for sensing, nanotrans-porting, nanomedicine, and logic-gate operations was suggested. For example, a DNA tweezer that captures, holds, and releases a molecular object was reported. Herein, we introduce an aptamer-based DNA tweezer. We demonstrate the coherent operation of two DNA tweezers in opposite directions, and we show that the system performs SET-RESET logic functions. The previously reported DNA tweezers were activated by a "fuel" DNA molecule that eliminated a component of the tweezer structure by formation of a duplex waste product, or by the cleavage of a nucleic acid component that is part of the tweezer by a DNAzyme unit integrated into the tweezer nanostructure. In both of the systems, the cyclic operation of the tweezers yielded DNA as a waste product, and the cyclic operation of the machines required the constant addition of fuel nucleic acids. In the present system, the DNA sequences stay intact throughout the cyclic operations of the nucleic acid tweezers.