High-Resolution, Three-Dimensional Investigation Of Protein Diffusion And Trafficking In The Live Hela Cell Via Interferometric Scattering Microscopy (Iscat)

Transmembrane proteins exhibit a wide variety of mobility in live cells, including diffusion in the plasma membrane and directed transport into the cell via endocytosis. Although a great deal has been uncovered about the biochemistry underlying these processes, their real-time visualisation in situ with the necessary nanoscopic resolution remains a daunting experimental challenge. Conventional microscopies rely on fluorescent labelling to monitor diffusion of such proteins within live cells. The resolution in both space and time by which one can successfully determine the position of the protein is curtailed by the finite and limited emission rate of the fluorophore.