Figure 4

Predicted nuclear flow in the stage 5 blastoderm. The movement of nuclei in three dimensions was estimated using PointCloud data derived from fixed embryo material. Three orthographic projections of this model are shown, illustrating movement dorsally (top), laterally (center), and ventrally (bottom). The length and direction of arrows indicate the direction and distance of nuclear movement. The position on the y-axis of the dorsal midline (D), ventral midline (V), and left (L) and right (R) lateral midlines are indicated. On the x-axis, anterior is to the left and posterior to the right. The scale is in μm from the embryo center of mass. The predicted movements broadly agree with those seen in the live embryos, being greater at the poles and dorsally than ventrally. Note that the apparent movement towards the center of each view results from the basal movement of nuclei inward.