title: Fast and ultrafast endocytosis.
abstract: Clathrin-mediated endocytosis (CME) is the main endocytic pathway supporting housekeeping functions in cells. However, CME may be too slow to internalize proteins from the cell surface during certain physiological processes such as reaction to stress hormones ('fight-or-flight' reaction), chemotaxis or compensatory endocytosis following exocytosis of synaptic vesicles or hormone-containing vesicles. These processes take place on a millisecond to second timescale and thus require very rapid cellular reaction to prevent overstimulation or exhaustion of the response. There are several fast endocytic processes identified so far: macropinocytosis, activity-dependent bulk endocytosis (ABDE), fast-endophilin-mediated endocytosis (FEME), kiss-and-run and ultrafast endocytosis. All are clathrin-independent and are not constitutively active but may use different molecular mechanisms to rapidly remove receptors and proteins from the cell surface. Here, we review our current understanding of fast and ultrafast endocytosis, their functions, and molecular mechanisms.
authors.affiliation: Department of Cell Biology, John Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD21205, USA; Solomon H. Snyder Department of Neuroscience, John Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD21205, USA. Electronic address: shigeki.watanabe@jhmi.edu.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Institute of Structural and Molecular Biology, Division of Biosciences, University College London, London WC1E 6BT, UK; Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck College, London WC1E 7HX, UK. Electronic address: e.boucrot@ucl.ac.uk.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Boucrot
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D002966:Clathrin / Q000378:metabolism; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D005089:Exocytosis; D013569:Synapses / Q000378:metabolism; D013572:Synaptic Vesicles / Q000378:metabolism
chemical_list: D002966:Clathrin