Figure 5.

Effects of compounds on SNARE-dependent lipid mixing. A–C, liposome fusion assays (see “Experimental procedures”) were conducted at 37 °C without or with 1 μm Munc13-4 + 400 μm Ca²⁺ and with 20 μm bexin-1 (A), 20 μm bexin-3 (B), or 20 μm bexin-5 (C). D, the indicated concentrations of compounds bexins-1, -3, and -5 were tested in the liposome fusion assay with Munc13-4 + Ca²⁺. E, liposome fusion assays were conducted without (open circles) or with Munc13-4 + Ca²⁺ (black circles) or with bexin-1 added at 0, 15, 37, or 55 min (shaded circles). F, SNARE complex formation was detected by fluorescence anisotropy (see “Experimental procedures”) in the presence of DMSO or 20 μm bexins-1 or -5. G, liposome fusion assays were conducted with no additions (Basal) or with 1 μm Syt1-C2AB + 400 μm Ca²⁺ or 5 μm Munc18-1 plus 20 μm of the indicated compounds. The final extent of lipid mixing is shown as mean values with a range of duplicate determinations. Studies are representative of three or more experiments.