Nicking enzyme-controlled toehold regulation for DNA logic circuits.

DNA strand displacement is widely used in DNA-related nanoengineering for its remarkable specificity and predictability. We report a nicking enzyme-assisted mechanism to regulate strand displacement, where DNA toeholds are dynamically controlled. To demonstrate the strategy, a protein/DNA-based Boolean operation system is constructed and based on it a two-channel multiplexer controlled by three different nicking enzymes is realized. The proposed regulatory mechanism can be used for switch logic statement and bridges protein and DNA logic circuits.