Photocontrolled DNA origami assembly using two photoswitches.

Stimuli responsive switching molecules have been widely investigated for the purpose of mechanical control of biomolecules. The recently developed arylazopyrazole (AAP) shows photoisomerization activity, displaying faster response to light induced conformational change and unique absorption spectral properties different from the conventionally used azobenzene. Here, we demonstrate that AAP can be used as a photoswitching molecule to control photo-induced assembly and disassembly of DNA origami nanostructures. We designed and constructed AAP-modified DNA origami. We observed the repeated assembly and disassembly of AAP-modified X-shaped DNA origami and hexagonal origami with counterpart complementary strands using alternative UV and visible light irradiation. Closed and linear assemblies of AAP-modified X-shaped origami were successfully formed by photoirradiation, and more than 1 µm linear assemblies were formed. Finally, we showed that the two photoswitches, AAP and azobenzene, can be used in tandem to independently control different assembly configurations using different irradiation wavelengths. AAP can extend the variety of available wavelengths of photoswitches and stably work for assembly and disassembly of various DNA origami nanostructures.