Table I. Analysis of cell motility of GDI1^– mutant.

	AX2	GDI1–
Speed (µm/min)	11.81 ± 3.15	11.04 ± 4.57
Persistence (µm/min × deg)	4.06 ± 1.87	4.09 ± 2.23
Directionality	0.80 ± 0.11	0.73 ± 0.23

Time-lapse image series were captured and stored on a computer hard drive at 30 s intervals. The DIAS software was used to trace individual cells along image series and calculate motility parameters. Persistence is an estimation of movement in the direction of the path. Directionality is calculated as the net path length divided by the total path length, and gives 1.0 for a straight path. Values are mean ± standard deviation of 76 (AX2) or 176 (GDI1^–) cells from at least three independent experiments. Both strains did not differ statistically in their motility behavior (Student’s t-test).