Y326F substitution in CAP impairs cell spreading on fibronectin. HeLa cells transfected with various CAP-EGFP constructs were allowed to adhere to fibronectin-coated coverslips for 25 min, then washed and fixed. The cells were scored on the basis of their spreading status as non-spread, half-spread or fully spread. WT CAP, Y360F or Y632F mutant showed no effect on cell spreading as compared to EGFP transfected cells, whereas Y326F mutant exhibited a slower spreading rate. The graph shows the results of 3 independent experiments with at least 100 cells scored in each. Error bars = SD.