Potential of Single‐Molecule Live‐Cell Imaging for Chemical Translational Biology

Abstract

Single-molecule live-cell imaging is the most direct approach for monitoring the motility of molecules in living cells. Considering the relationship between the motility of molecules and their function, information obtained from single-molecule imaging involves essential clues for understanding the regulatory mechanisms of the processes of target molecules, and translation to applied sciences such as drug discovery. In this Concept, examples of single-molecule imaging studies on G protein-coupled receptors (GPCRs) are mainly introduced, and recent techniques of single-molecule imaging for overcoming the limitation of single-molecule live-cell imaging are discussed.Based on these studies, the prospects of single-molecule imaging will be outlined.

Triple-color single-molecule imaging for analysis of the role of receptor oligomers in signal transduction

“…Since the depth of evanescent light produced by total internal reflection illumination can reach just the vicinity of the basal plasma membrane of the sample cell, molecules in and on the plasma membrane like receptors are suitable targets for single-molecule imaging studies. Various findings have been obtained on the mechanism of extracellular signal transduction through receptor molecules based on the analysis of receptor motility [10][11][12].…”

“…For example, single-molecule imaging-based observation was performed on cluster formation of chromatin structure components. RNA, in addition to protein, is becoming a target for single-molecule imaging in living cells due to the development of fluorescent labeling methods on endogenous RNAs in living cells [12,[38][39][40][41]. Moreover, a technology to overcome the limitation of observation time due to the photobleaching was developed, and single-molecule motions during target cellular events were now possible to be tracked continuously over several minutes [42].…”