Figure 1.
Lipid composition of the vesicle and target membrane affects docking and fusion of Syb2 vesicles in single vesicle to planar supported membrane fusion assay. (A) Mean final docking after saturation of reconstituted acceptor SNARE complex-containing target membranes with Syb2 vesicles. Numbers of docked vesicles per μm2 are average values of 16–18 independent experiments (different bilayers), in which the final docking densities were obtained by fitting Eq. 1. Error bars represent standard deviations of the mean final docking density between different bilayers. (B) Fusion probability calculated as the percentage of observed total fusion events over all recorded docking events. Error bars represent standard deviations from all measurements in multiple membranes of the same lipid composition. The “extracellular” leaflets in all supported target membranes were composed of POPC/Chol (4:1), whereas the “cytoplasmic” leaflets contained in addition different concentrations of DOPS and DOPE as indicated. These lipids were added to vesicle and target membranes (gray bars) or to vesicle membranes only (black bars).