title: Reconstitution of Synaptic SNAREs into Large Liposomes with Reduced Curvature Stress.
abstract: Liposomes constitute a convenient biochemical model system to investigate mechanistic aspects of the membrane fusion of synaptic vesicles. The proteins responsible for mediating fusion are the SNAREs that belong to a highly conserved family of transmembrane proteins. Reconstituting SNAREs into liposomes using detergents has become a common approach not only to understand how SNAREs work, but also how fusion is regulated by the vast array of accessory proteins present at the presynapse. However, a concern has been that the high curvature stress of the small liposomes (diameters of ~40 nm) frequently used in many studies renders them prone to spontaneous fusion, bringing into question whether the measurements obtained faithfully represent SNARE-mediated fusion. By systematically varying the detergent concentration and characterizing the SNARE-liposome size distributions by light scattering, we describe a detailed procedure to reconstitute SNAREs into large liposomes with considerably reduced curvature stress.
authors.affiliation: Department of Structural Biochemistry, Max Planck Institute for Molecular Physiology, Otto-Hahn-Str. 11, 44202, Dortmund, Germany. matias.hernandez@mpi-dortmund.mpg.de.
authors.forename: Javier M
authors.initials: JM
authors.lastname: Hernandez
mesh_terms: D005089:Exocytosis; D008081:Liposomes / Q000737:chemistry* / Q000302:isolation & purification; D008561:Membrane Fusion; D050600:SNARE Proteins / Q000737:chemistry* / Q000378:metabolism*; D009435:Synaptic Transmission; D013572:Synaptic Vesicles / Q000378:metabolism*
chemical_list: D008081:Liposomes; D050600:SNARE Proteins
keywords: Exocytosis; Liposome; Membrane fusion; Neurotransmitter release; SNARE