title: A balance between membrane elasticity and polymerization energy sets the shape of spherical clathrin coats.
abstract: In endocytosis, scaffolding is one of the mechanisms to create membrane curvature by moulding the membrane into the spherical shape of the clathrin cage. However, the impact of membrane elastic parameters on the assembly and shape of clathrin lattices has never been experimentally evaluated. Here, we show that membrane tension opposes clathrin polymerization. We reconstitute clathrin budding in vitro with giant unilamellar vesicles (GUVs), purified adaptors and clathrin. By changing the osmotic conditions, we find that clathrin coats cause extensive budding of GUVs under low membrane tension while polymerizing into shallow pits under moderate tension. High tension fully inhibits polymerization. Theoretically, we predict the tension values for which transitions between different clathrin coat shapes occur. We measure the changes in membrane tension during clathrin polymerization, and use our theoretical framework to estimate the polymerization energy from these data. Our results show that membrane tension controls clathrin-mediated budding by varying the membrane budding energy.
authors.affiliation: Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Saleem
authors.affiliation: Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Morlot
authors.affiliation: Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland.
authors.forename: Annika
authors.initials: A
authors.lastname: Hohendahl
authors.affiliation: PCC, UMR168, Institut Curie/CNRS/Université Pierre et Marie Curie, F-75248 Paris, France.
authors.forename: John
authors.initials: J
authors.lastname: Manzi
authors.affiliation: University LPTMS, UMR 8626, CNRS/Université Paris Sud, Orsay F-91405, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Lenz
authors.affiliation: 1] Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland [2] Swiss National Centre for Competence in Research Programme Chemical Biology, CH-1211 Geneva, Switzerland.
authors.forename: Aurélien
authors.initials: A
authors.lastname: Roux
mesh_terms: D000818:Animals; D002966:Clathrin / Q000737:chemistry*; D003034:Coated Pits, Cell-Membrane / Q000737:chemistry* / Q000648:ultrastructure; D004548:Elasticity; D008840:Microfilament Proteins / Q000378:metabolism; D008958:Models, Molecular; D009995:Osmosis; D058105:Polymerization; D034421:Sus scrofa; D013816:Thermodynamics; D053835:Unilamellar Liposomes / Q000378:metabolism
chemical_list: D002966:Clathrin; D008840:Microfilament Proteins; D053835:Unilamellar Liposomes