Combination Analysis of Fluorescence Single-Molecule Imaging with Other Microscopic Techniques Elucidates Actin Turnover Mechanisms in Living Cells

Abstract

Fluorescence single-molecule speckle microscopy is a powerful tool to elucidate intracellular dynamics of cytoskeleton-associated molecules. However, it is often difficult to precisely understand how the observed molecule behave as a whole in the system. On the other hand, imaging approaches such as FRAP (fluorescence recovery after photobleaching), which visualize redistribution of bulk population of the molecule, has limited spatiotemporal resolution, leading to imperfect interpretation by overlooking a minor population of molecular species with distinct kinetics. We will introduce our recent studies in which combination analysis of fluorescence single-molecule imaging with FRAP or s-FDAP (sequential-fluorescence decay after photoactivation) provided better understanding in the regulation of actin polymerization and depolymerization cycles.