Figure 3.

Time trace of a two-color fusion experiment, demonstrating that content transfer and lipid-mixing occur simultaneously. Docking occurs at t ≈ 100 ms, indicated by the appearance of the TR signal (red trace). The self-quenched content dye in the SUV (green trace) is not visible over the noise. After a delay of ∼480 ms during which the TR undergoes some photobleaching, full fusion is observed at t ≈ 580 ms, by content dye dequenching (compare to Fig. 2) followed by a rapid drop in the intensity of both dyes as they diffuse away.