Endocytic Clathrin Structures in Live Cells were ImagedAuthor(s): Diana Smith
New visualization techniques have greatly aided our understanding of the clathrin-dependent endocytic mechanism. Budding coated pits and clathrin-coated structures are ephemeral molecular machines with distinct morphological features, and fluorescently tagged versions of a range of marker proteins have provided a tantalizing view of the system's dynamics in living cells. Recent live-cell imaging studies have shown unanticipated modalities of coat building, with distinct kinetics, recruitment of related proteins, actin, and accessory protein participation requirements, and membrane deformation mechanisms that appear to be distinct. Connecting the events seen by light microscopy with the structures and characteristics of the molecular constituents is a critical challenge. In this paper, I present descriptions of coat construction in several situations that are consistent with what has been learned through X-ray crystallography and electron microscopy.