title: ENDOCYTOSIS. Endocytic sites mature by continuous bending and remodeling of the clathrin coat.
abstract: During clathrin-mediated endocytosis (CME), plasma membrane regions are internalized to retrieve extracellular molecules and cell surface components. Whether endocytosis occurs by direct clathrin assembly into curved lattices on the budding vesicle or by initial recruitment to flat membranes and subsequent reshaping has been controversial. To distinguish between these models, we combined fluorescence microscopy and electron tomography to locate endocytic sites and to determine their coat and membrane shapes during invagination. The curvature of the clathrin coat increased, whereas the coated surface area remained nearly constant. Furthermore, clathrin rapidly exchanged at all stages of CME. Thus, coated vesicle budding appears to involve bending of a dynamic preassembled clathrin coat.
authors.affiliation: Cell Biology and Biophysics Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. Structural and Computational Biology Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany.
authors.forename: Ori
authors.initials: O
authors.lastname: Avinoam
authors.affiliation: Structural and Computational Biology Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. Electron Microscopy Core Facility, The European Molecular Biology Laboratory, Heidelberg 69117, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schorb
authors.affiliation: Cell Biology and Biophysics Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany.
authors.forename: Carsten J
authors.initials: CJ
authors.lastname: Beese
authors.affiliation: Structural and Computational Biology Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. Cell Biology and Biophysics Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. marko.kaksonen@unige.ch john.briggs@embl.de.
authors.forename: John A G
authors.initials: JA
authors.lastname: Briggs
authors.affiliation: Cell Biology and Biophysics Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. Structural and Computational Biology Unit, The European Molecular Biology Laboratory, Heidelberg 69117, Germany. marko.kaksonen@unige.ch john.briggs@embl.de.
authors.forename: Marko
authors.initials: M
authors.lastname: Kaksonen
mesh_terms: D002460:Cell Line; D002966:Clathrin / Q000737:chemistry*; D003034:Coated Pits, Cell-Membrane / Q000737:chemistry*; D055032:Electron Microscope Tomography; D004705:Endocytosis; D036681:Fluorescence Recovery After Photobleaching; D006801:Humans; D008856:Microscopy, Fluorescence
chemical_list: D002966:Clathrin