Movie 3

Venus::CYK-1 (yellow) accumulation in juxta-apical punctae is greatly reduced in cdc-42(0*). Arrows mark the first appearance of punctae that were visible for at least two frames (~60 seconds). In this ~10-minute movie we only found 2 such punctae, and both were found near the basolateral domain, not juxta-apical (compare to wild-type Movie S1). F-actin, labelled with LifeAct::TagRFP (magenta), is found at the lumen-lining apical membrane and can be seen accumulating in some motile punctae, although most are not marked with Venus::CYK-1 and their localization is more variable than in wild-type. This movie is a maximum projection of four 1μm z-steps taken using the settings for Venus::CYK-1 described in the “Spinning Disk Microscopy Settings” section of the Supplementary Materials and Methods.