Fig. 2. Soluble ephrins destabilise neural crest cell lamellipodia. (A) Neural crest cells were examined using timelapse videomicroscopy for 30 minutes and then stimulated with 2 µg/ml pre-clustered ephrin-B2-Fc for 45-60 minutes. The withdrawal of neural crest cell lamellipodia (red arrow) was associated with membrane ruffling (red arrowhead) following contact with the ephrin-B2-Fc stripe. (B) Membrane ruffling led to the internalisation of phase bright vesicles. (C) Lamellipodial dynamics were analysed by kymography prior to stimulation (15.5±1.2 peaks/hour) and in the presence of 2 µg/ml pre-clustered ephrin-B2-Fc (25.2±1.1 peaks/hour); in the presence of ephrin-B2-Fc the lifetime of protrusions was decreased (P<0.05, n=9). A representative kymograph from a total of nine neural crest cells examined is shown (three separate timelapse movies). (D) A trace of the kymograph shown in C. Bars, 10 µm.