Fig. 5. (A) The development of -actinin motile projections in living MCF-7/IGF-IR/WT cells stimulated with IGF-I. Dynamics of EGFP--actinin in live MCF-7/IGF-IR/WT cells transiently transfected with WT -actinin-EGFP encoding plasmid. (A-C) The representative laser confocal fluorescence images taken at the apical, middle and basal focal planes in serum-starved cells (a,d,g) stimulated with 50 ng/ml IGF-I for 5 minutes (b,e,h) or for 9 minutes (c,f,i) are shown. Circled is an example of a cell that is flattening, separating and moving from the adjacent cells in response to IGF-I treatment. The optical section from the apical region was taken about 2.0 µm from the top of cells. The example of the lateral single projection that extended and folded over the cell apex is indicated by arrow in a-c. The middle optical sections were collected from the focal plane about 6.5 µm from the top of cells. Basal images were taken close to the substratum level (about 1.5 µm from the glass surface). Bar, 10 µm.

(B) Reorganization of -actinin is blocked in living MCF-7/IGF-IR/DK cells treated with IGF-I. The images illustrate the localization of -actinin in live MCF-7/IGF-IR/DK cells transfected with EGFP-labeled -actinin before (0 min) and after IGF-I stimulation (shown for 1 and 5 minutes). The representative images derived by 3D projection of 20 consecutive apical and middle optical sections are shown. Bar, 10 µm.