Figure 3.
(Left) Time-resolved fluorescence intensity traces of DiD-C18-marked CGs (red) upon docking and fusing with Atto488-DPPE-labeled PSMs (green) doped with the ΔN49 complex. The time period of post-lipid-mixing is shaded in yellow. The magenta dotted lines mark the time points of CG collapse. The black dotted lines mark the fluorescence intensities of the baselines. Of note, in (B), two different baselines are given, one referring to the s-PSM and the other one to the f-PSM at which the CG has fused. (Right) Fluorescence micrographs of the corresponding intensity curves showing the last frame before the onset of lipid mixing (pre-lipid-mixing), the frame when lipid mixing starts (t = 0), and the last frame of the time series (post-lipid-mixing) are shown. The diffusion trajectories of the CGs before (white) and after (yellow) lipid mixing are depicted as solid lines. The position of the CG is highlighted with a dashed circle; scale bars, 2 μm. (A) A fusion event with a stable three-dimensional post-lipid-mixing structure is shown. (B) A fusion event with a delayed collapse of the CG is shown. (C) A fusion event with a fast collapse of the CG is shown. To see this figure in color, go online.