Figure 2.

Schematic representation of the local stimulation protocols. A. Pipette 5–8 µl of solution containing lipid vesicles into the imaging chamber, wait for them to sink and trap one of them by focusing the IR laser in the center of the vesicle. B. Gently move the trapped lipid vesicle in the proximity (10–20 µm) of the cell compartment (growth cone (black line) in this case) to stimulate, with an angle between 0–90^°. C. Break the lipid vesicle to release its content and locally deliver the protein to the growth cone. In this case, a repulsive cue triggers collapse and retraction from the source (red line depicts putative morphological change after stimulation). D. Same as in (A), but pipette 5–8 µl of coated beads into the chamber. E. Gently move the trapped bead over the cell compartment (central part of the growth cone (black line) in this case) to stimulate and leave it there for the chosen amount of time. F. In this case, a repulsive cue mediates collapse and retraction of the stimulated region (red line depicts putative morphological change after stimulation).