Fig. 2: Follicle cell expansion behavior involves systematic changes in Rac1/Rho1 activities and basal actomyosin networks associated with ruffles, area and focal adhesions.

a, d, g, j, m Time-lapse basal PAK3RBD-GFP and LifeAct-RFP images (heatmap) during the ruffling phase (a), basal AniRBD-GFP and LifeAct-RFP images (heatmap) during the ruffling (d) and spreading (g) phases, and Talin-GFP and LifeAct-RFP images (heatmap) during the ruffling (j) and spreading (m) phases. White dotted lines mark the local membrane boundary in (a, d) and the whole cell boundary in (g). White dotted lines mark a local ruffling-associated area region in (j) and the whole cell boundary in (m), arrow marks migration direction in (m), and asterisks show the arrival of the pulsed signals at anterior region in (m). RGB bars mean signal intensities in (a, d, g, j). b, e, h, k, n Quantifications of dynamic local changes of Rac1 activity, ruffling-associated subcellular basal area and F-actin signals in follicle cells during the ruffling phase (b), Rho1 activity, ruffling-associated basal area and F-actin signals in follicle cells during the ruffling (e) and spreading (h) phases, and basal area, Talin and F-actin signals in follicle cells during the ruffling (k) and spreading (n) phases. c, f, i, l, o Quantifications of the time offset of different indicated signals during the ruffling phase (c), the ruffling (f) and spreading (i) phases, and the ruffling (l) and spreading (o) phases. p, q Representative cartoons to summarize the temporal cascade composed of Rac1 activity, ruffling-associated area increase, Rho1 activity, basal actomyosin networks, and focal adhesions locally (labeled by different colors) in follicle cells during the ruffling (p) and spreading (q) phases. Scale bars are 10 μm in (a, d, g, j, m). The dashed lines in (b, e, h, k, n) indicate the peaks of corresponding color-marked signals within one cycle. The middle line indicates the median, and floating bars shows the minimum to maximum, of n = 20, 20, 20, 10, 15 independent cells in (c, f, i, l, o). All P values have been listed in Supplementary Note 1. Source data are provided as a Source Data file.