Fig. 8. Dynamics of cell spreading on fibronectin dots of 0.1 µm². Images of a time-lapse sequence of a B16 cell expressing ß3-integrin-GFP (ß3-GFP) growing on a patterned substratum of 0.1 µm² fibronectin dots. Dots were visualised by mixing the fibronectin with fluorescently labelled BSA. Since ß3-GFP cells display homogeneous background fluorescence, they were used in these assays to reveal cell morphology. The cell was highly motile but did not spread. A few minutes after initial contact, a dot (arrows in A-F) was first stretched (arrow in C), removed from the substratum (arrowhead in D) and then internalised into the cell (arrowheads in E and F). This behaviour results in a rearranged dot pattern after a cell has migrated over that area. Time is given in minutes and seconds. Scale bar: 10 µm.