Cytoskeletal and PM coordination during periodic protrusions. (A) Predictions of fluorescent signal outcome based on two different models for rounded protrusions. Schematic drawing presents cell top view (left) and plot of fluorescent signals within the rectangle (right) of cortical F-actin (green) and PM (red). (B) Time-lapse confocal fluorescent images of a cell transfected by Lifeact-GFP (green) and PMT-mRFP (red; Video 2). The yellow rectangles (33 × 1 µm) show the positions where the fluorescent signal was analyzed. To the right of the images are plots of averaged line scans of fluorescence intensity going from the left to the right. (C) Correlation plot between maximum intensity of F-actin and PM fluorescence at the cell periphery presented in B (correlation coefficient R = 0.95). In total, n = 31 cells from 12 experiments were analyzed. For each cell, 20 consecutive frames were analyzed and each frame provides two positions for correlation analysis where the rectangle intersects the cell margin; the arrows in B (top right) denote examples of chosen positions (vertical arrows for cortex; oblique arrows for PM). Time shown in seconds.