Figure 1.

Determination of the optimum collagen concentration for T47D random cell migration. Control T47D cells and cells expressing activated R-Ras (38V) were plated on various concentrations of collagen-coated Petri plates for 1 h. Time-lapse microscopy sequences were acquired for 30 min, with one image collected per minute. The movies were then analyzed by counting the number of cells migrating in the field and relative migration expressed as the number of migrating cells/total number of cells. Altering collagen concentration had no effect on cell migration by R-Ras (38V)-expressing cells. Control cells, solid line; R-Ras (38V)-expressing cells, dashed line.