Fig. 2. Dynamics of IRSp53 in B16 melanoma cells. (a-d) B16 melanoma cell cotransfected with EGFP-IRSp53 and dominant active Rac1V12. The dynamics of bracketed areas in (a,b) are represented as (c,d), respectively. In (c,d) white lines indicate a region of protrusion (arrows) preceded by ruffling (asterisks). Phase dense area corresponding to the lamellipodium region extending parallel to the substrate is indicated by brackets in (c,d). (e,f) B16 cell expressed EGFP-IRSp53 and stimulated by treatment with aluminium fluoride 15 minutes before image acquisition. IRSp53 was not retained in retraction fibres (arrowheads) and retracting ruffle (arrows). Time is given in minutes and seconds. Bars, 10 µm.