Fig. 4.

CAPS promotes stable docking of VAMP2 liposomes to t-SNARE supported bilayers. Bilayers containing t-SNAREs and 5% PIP₂ were incubated with Rh-PE labeled VAMP2 liposomes (A) or additionally with 1 μM CAPS (B), 5 μM soluble syntaxin (C), or CAPS with soluble syntaxin (D). Protein-free Rh-PE liposomes were incubated with bilayers (E) or co-incubated with 1 μM CAPS (F). Bilayers were washed and imaged by TIRF microscopy, and the number of docked liposomes per field (6,300 μm²) was quantified for 7 different regions for each condition (means with range of duplicates shown for 2 experiments).