The visualization of biomolecules is a straightforward way to elucidate the physical properties of molecules and their reaction processes. Atomic force microscopy (AFM) enables the direct imaging of biomolecules under physiological conditions at nanometer-scale spatial resolution. Because AFM visualizes all molecules in a scanning area, an observation scaffold is required for the target-specific imaging of molecules in the dynamic state. The DNA origami technology allows the precise placement of target molecules in a designed nanostructure, and the detection of the molecules at the single-molecule level. DNA origami is applied for visualizing the detailed motions of molecules using high-speed AFM (HS-AFM), which enables the analysis of the dynamic movement of biomolecules in a subsecond time resolution. Here, we describe the combination of the DNA origami system with HS-AFM for the imaging of DNA structural changes controlled by photoresponsive molecules. The hybridization and dehybridization of photoresponsive oligonucleotides were visualized directly using this observation system. These target-oriented observation systems should contribute to the detailed analysis of biomolecules in real time with molecular resolution.
Endo, M., & Sugiyama, H. (2018). Direct observation of dynamic movement of DNA molecules in DNA origami imaged using high-speed AFM. In Methods in Molecular Biology (Vol. 1814, pp. 213–224). Humana Press Inc. https://doi.org/10.1007/978-1-4939-8591-3_13