Movie S2.

Time-lapse image of a centered, triple-labeled HIV particle challenging a cell. Plotting of the measured mean intensities with background subtracted (y axis) within the voxels of the tracked individual particle is shown. (Left) Two drops of GFP signal are discerned in the presence of Vpr while S15 signal is lost, which shows fusion happens concurrently with the first drop of the GFP signal. (Top Right) Particle box shows the signal of GFP (green), Vpr (red), and S15 (blue) over time. (Bottom Right) Smaller boxes show the signal (gray) of each individual fluorescence measurement as labeled.