FIGURE 5.

Ca²⁺-dependent proteoliposome fusion in vitro. A, vesicles harboring t-SNAREs, WT syb2, POPE-linked syb2 ΔTMD constructs, or protein-free liposomes were separated by SDS-PAGE and stained with Coomassie Blue. Note that ΔTMD-CSPα has a higher molecular mass due to the CSPα motif and multiple acyl lipids. B, representative fusion traces from reactions involving v-SNARE vesicles harboring either WT or lipid-anchored syb2 and 1 μm of the cytosolic C2AB domain of synaptotagmin 1. Reactions were performed with additions of EGTA or Ca²⁺ at the arrow. Including ΔTMD-94 (5 μm) demonstrated SNARE dependence of fusion. Representative data are shown from 2 to 3 independent experiments.