Fig. 2. Effects of calpain inhibition on the dynamics of GFP-vinculin (A,B) and GFP/RFP-zyxin (C-F) in CHOK1 cells plated on fibronectin (10 µg/ml). Video sequence of magnified regions of cells co-transfected with GFP-vinculin and control vector (A) or calpastatin (B), co-transfected with GFP-zyxin and control vector (C) or calpastatin (D), or co-transfected with RFP-zyxin and hrEGFP (E) or hrEGFP-calpastatin (F). Frames are from 6 minute intervals (t=0, 6, 12, 18, 24 and 30 minutes). GFP-vinculin and GFP- or RFP-zyxin-containing adhesions in cells that expressed calpastatin (B and D/F, respectively) are larger, more peripheral and stabilized. White arrows show position of adhesive contact sites that were stabilized. In comparison, control cells have smaller more dynamic GFP-vinculin and GFP-zyxin-containing adhesions. Open arrows show the position of representative contacts sites that turnover. Representative images from a minimum of five separate experiments with more than 10 cells viewed per condition (Movies 1-6). Bars, 10 µm.