Fig. 2. Filopod formation, retraction and relocation for a representative cell migrating in buffer. (A) Reconstruction of the full cell, including nucleus, pseudopodia and filopodia. (B) Reconstruction only of pseudopodia and filopodia. The cell is viewed from the top (90°). Time is presented in seconds (sec). The arrows at 0 and 108 seconds in panel A reflect changes in orientation of the posterior-anterior axis during the time of analysis. See legend to Fig. 1B for color code. A, anterior end of cell; U, uropod; a, b, c, d, e, f, g, pseudopods in order of appearance. Note that the long yellow tail fiber is much longer than shown, and is truncated by the area of view and that the uropod and long tail fiber are stable throughout the period of analysis. Note also that the starred filopodia on the cell body in panel A, 40 sec, originated on pseudopod a and that the starred filopod on the cell body in panel A, 56 sec, originated on pseudopod c.