FIGURE 7.

Akt1 KO cell adhesion is impaired independently of β1 integrin expression and activation. A, cell adhesion on various concentrations of fibronectin-coated wells in the presence or absence of Mn²⁺ was measured at 1 h. The adhesion defect of Akt1 KO fibroblasts did not improve by the addition of Mn²⁺ on the highest concentration of fibronectin (FN). In contrast, DKO fibroblasts displayed increased adhesion. B, β1 integrin surface expression was similar in all cell types. In addition, the ratios of active α5β1 integrin (measured by FN9-11) to total β1 integrin levels were equal in all cell types (C). D–F, cells were allowed to adhere to 1.5, 12, or 24 μg/ml fibronectin-coated wells, and adhesion was measured at 1, 3, 6, 12, and 24 h. Akt1 KO cells displayed improved adhesion only at 24 h at the highest concentration of fibronectin (24 μg/ml). AU, arbitrary units. Data are expressed as the average ± S.E. (error bars). *, p ≤ 0.05.