Fig. 1. Dictyostelium cells migrate directionally in an electric field. (A,B,C) Trajectories plotting the movement of the cell centres of AX2 cells in (A) the absence of an electric field, (B) the presence of an electric field and (C) following reversal of field polarity. (B',C') Consecutive micrographs show migration of cells in an electric field of 15 V/cm. (supplementary material Movie 1). Numbers in A-C' indicate individual cells.