Professor Takayuki Uchihashi, Department of Physics/ Institute for Glyco-core Research (iGCORE), Nagoya University, Nagoya, Japan & The Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Japan 

Dynamic Structural Biology Driven By High-Speed Atomic Force Microscopy
Most biological phenomena in the cell are elicited by a cascade of extensive dynamic molecular processes, including protein conformational changes, binding and dissociation, assembly and degradation. A fundamental understanding of complex biological processes is inherently reducible to understanding the dynamics of a small number of molecules at each step in such a cascade. Since protein motions are usually asynchronous and often have a multimodal distribution that cannot be directly assessed by ensemble averaging methods, it is necessary to monitor and analyze the dynamic behavior of individual molecules using a dynamic structural biology approach based on single molecule observation. Among various microscopic techniques for characterizing protein structures and functions, high-speed atomic force microscopy（HS-AFM）is a unique technique in that allows direct visualization of structural changes and molecular interactions of proteins without any labeling in a liquid environment. Since its emergence in 2001¹⁾, it has been applied to the dynamics analysis of various types of proteins, including motor proteins, membrane proteins, DNA-binding proteins, amyloid proteins, and artificial proteins^{2), 3)} and now has now become a versatile tool indispensable to drive research  based on dynamic structural biology.

In this talk, I will review several recent bioimaging applications realized by HS-AFM and show what kind of dynamics phenomena can be observed by HS-AFM.  This review provides overviews of several recent bioimaging applications achieved by HS-AFM, classified into imaging studies of conformational dynamics and protein-protein interactions. Recent instrumental developments to extend the capabilities of HS-AFM, especially molecular manipulation by localized force application, one of the key features of AFM, will also be discussed.

1. T. Ando et al,PNAS 98, 12468-12472 (2001)
2. T. Ando, T. Uchihashi, S. Scheuring, Chem. Rev. 114, 3120-3188 (2014)
3. T. Uchihashi and C. Ganser, Biophys. Rev.12, 363-369 (2020)

Biography
Takayuki Uchihashi is a professor of Physics Department at Nagoya University since this spring. He received his B. Sc., M.Sc. in Physics from Hiroshima University in 1993 and 1995, respectively. In 1998, he obtained Dc. Eng. in Electronics from Osaka University. From 1998 to 2000, he worked at Joint Research Center for Atom Technology (JRCAT) in Tsukuba as a research associate. In 2000, he moved to Department of Electronic Engineering, Himeji Institute of Technology as an assistant professor. After that he moved to Trinity College in Dublin in 2002 and worked as a senior researcher in SFI Nanoscience Institute. In 2004, he joined the Physics Department, Kanazawa University as an assistance professor. He became an associate professor in 2008, and a full professor in Physics Department in 2015. He was also appointed the director of Bio-AFM Frontiers Research Center in Kanazawa University for the last two years. In 2017, he moved to Department of Physics, Nagoya University. His research interests include the instrumentation of scanning probe microscopy and its application to biological science.