3D imaging of actin and vesicles. Markers are shown to the left of panels. 3D perspective is indicated at the bottom right panel corners. (A–H) Phalloidin in fixed embryos. Arrows, arrowheads, and asterisks show individual actin puncta that correspond in each rotation (A–F). (G and H) Boxes show the region considered the central spindle for quantifications. (I) Live series of α-Tub and rhodamine-actin. Time points (s) are indicated at the bottom right of each panel. Images were cropped at the furrow (arrows) and rotated 45° to show xy and z planes. Arrowheads indicate actin puncta colocalized with MT bundle. Dotted bracket indicates central spindle. (J) Genotypes and markers are shown at the top right and cell number (n) is shown in bars. Error = SEM. Center region in the right graph includes the middle one-third of the cell in the xy plane. (K and L) Dah-positive vesicles localize to furrow MTs (arrows) and central spindle MTs (arrowheads). Arrows and arrowheads correspond to same vesicle in each rotation (L and M). Step size = 150 nm, except I (200 nm). Bars: (A and G–L) 3 μm; (B, C, and M) 2 μm; (D–F) 1 μm.