Figure 3

First quartet micromeres generate anterior ectoderm and prototroch. (A-D) Single-channel, z-stacks of confocal images of late stage 6 larvae from an anterior view 5 days after labeling first quartet micromeres with DiI (white). The stacks start at the anterior ectodermal surface and end just posterior to the prototroch. (E-H) Z-stacks of merged, confocal images through a subset of the brain in late stage 6 larvae. The channels are DiI (red), phalloidin (green) and TO-PRO-3 (blue). (E, F) Labeled brain cells positioned ventral to the cerebral commissure are indicated with an arrowhead in (E,F). (I-J) Digital magnification of the eye region bracketed in (E) and (G), respectively. One side of the eye sensory cell is outlined with a dashed line. (K-L) Z-stacks of merged, confocal images through the entire brain of late stage 6 larvae. The channels are DiI (red) and TO-PRO-3 (blue). The blastomere labeled with DiI is indicated in the upper-right corner, and the view is indicated in the lower-left corner of each panel (ant = anterior). All images are from an anterior view, with ventral down. The position of the mouth is indicated with an asterisk. br = brain, cm = brain commissure, pc = pigment cell, sc mv = sensory cell microvilli.