Fig. 7. Defective turnover of focal contacts in DEP-1-expressing cells. (A) Large well-developed focal contacts can be seen at the leading edge of control fibroblasts. DEP-1 expression results in cells that generate only small focal adhesions, possibly focal complexes, at the very margins of the leading lamellipodium. (B) The unstable nature of these adhesions was quantified as described and is shown as a persistence index in which a high persistence directly equates to stability of the adhesions. Mean persistence index ± s.e.m.; Student's paired t-test shows no significant differences between 1A2 cells plus or minus treatment with mifepristone, and P<0.01 between control 2D3 cells and 2D3 plus mifepristone.