Fig. 3: Macropinocytosis leads to cell size reduction.

a Time lapse of a macropinocytotic event in tissue labeled with Lifeact-FP. The dotted line represents cell original size, highlighting the cell size reduction. Scale bar 10 μm. b Quantification of cell size change in cells with (blue) or without (red) a macropinocytotic event (MP) using cells synchronized to the onset of macropinocytosis and normalized to original cell size (n = 3 exp. and 43 cells total; mean and SD). c Correlation between the apical size reduction and the size of actin ruffle (n = 3 exp. and 43 cells). d Quantification of the change in junction length in cells with and without macropinocytosis (n = 4 exp. and 40 cells; two-sided unpaired t-test, p-value = 1.23e-07). e Graphical depiction of a cell with different junction types labeled (N1-N4) in different colors based on their distance from the macropinocytotic event. f CellFit analysis of time lapse movies quantifying the change in relative junctional tension before and after macropinocytosis (n = 25 events; see Fig. S1f; box = interquartile, center line = median, error bars = min/max; two-sided paired t-test of before and after the event p-value N1 = 0.0001, N2 = 0.0281, N3 = 0.4890, N4 = 0.3492). g Model comparing the effect of cell extrusion (center) or macropinocytosis (right) occurring in the cell (asterisk) of a crowded epithelium (left). Blue color highlights the putative effect on cells/neighbors. Source data are provided as a Source Data file.