Figure 4.

Haptotactic migration assay of control and myosin IIB mutant cells. To measure haptotactic movements, cells were plated on porous membrane with one side coated with collagen or fibronectin, at a concentration of 40 and 20 μg/ml, respectively. Random migration was measured by applying this coating to both sides of the membrane. The number of cells that migrated across the membrane was counted after 15 h. Bars represent the mean ± SE from six independent experiments. For either collagen or fibronectin coating, myosin IIB null cells show no significant haptotactic migration. To the contrary, control cells show a haptotaxis/random migration ratio of 5–6.