Direct observation of the dual-switching behaviors corresponding to the state transition in a DNA nanoframe.

To create a nanoscale dual switch, two responsive DNA motifs, azobenzene-modified DNAs and G-telomeric repeat sequences, were introduced together into the nanoframe system. The dualswitching behaviors controlled by photoirradiation and K+ were successfully visualized in real time by high-speed atomic force microscopy. [ABSTRACT FROM AUTHOR]