Fig. 7. Treatment with an activator of RhoA restores motility on fibronectin and actin polymerization of ST6GalNAc I transfectants. (A) STn-control cells and STn+ ST6GalNAc I transfectants were pretreated for 30 minutes with TATRhoA^Val-14 protein (V14), a RhoA activator at 6 µg/ml, before being seeded on immobilized fibronectin at 10 µg/ml (FN) or on hyaluronic acid at 5 µg/ml (HA). Motility was tested in a phagokinetic track assay, and results from one representative experiment out of two are shown. Error bars correspond to the standard deviation of the mean of triplicates. (B) Quantitative analysis of morphological parameters was performed on STn- and STn+ cells transduced with the constitutively active TAT-RhoA^Val-14 protein (V14), with the inactive TAT-RhoA (N19) or untreated (controls). Cell area and perimeter were acquired for each cell type and the shape factor (f) was calculated as described in Materials and Methods. Error bars represent the standard deviation for 100 cells. (C) Staining of actin stress fibers was performed using rhodamine-labeled phalloidin on fixed and permeabilized STn- and STn+ cells cultivated on glass lamellae. Cells were treated with 6 µg/ml TAT-RhoA^Val-14 protein (TAT-RhoA^Val-14 protein) for 16 hours before fixation.