Quantification of collective ERK activation in a 7-d-old MCF10A WT acinus. (A) Snapshots of a single CE. Top row—maximum projection of the ERK-KTR channel; middle row—cell nuclei shaded according to detrended and normalized ERK activity; bottom row—nuclear centroids colored by ERK activity and sized according to z distance. Black dots indicate active cells. Scale bar, 10 μm. (B) Heatmap of ERKATS ordered along the y-axis. Each row corresponds to a single cell. (C) Spaghetti plot of CEs during the entire acquisition. The dashed rectangle indicates the space–time section from A.