Pk1 puncta alternate with F-actin densities. (A) PCM expressing Pk1-venus and LifeAct-Ruby. Alternating localization of Pk1 plaques (white arrows) and F-actin dense regions (yellow arrows). Scale bar, 10 μm. (A′) Intensity plots of Pk1 (green) and F-actin (red) along cell membrane. (B) Cells in Pk1-venus and LifeAct-Ruby expressing PCM treated with Arp2/3 inhibitor CK666. Large Pk1 patches are surrounded by F-actin bundles (arrows). Below the surface, Pk1 plaques at cell–cell contacts; diffuse Pk1 distribution unchanged. Scale bars, 10 μm.