Morphology of the IP Cells.

IP1-1, IP1-2 and IP1-3 type 5HT cells shown in single-cell or two-cell flp-out clones via anti-CD8 (green), anti-5HT (red) and anti-FasII/anti- ChAT (blue) staining (A, E and I). The three channels are presented individually in panels B–D, G–H and J–L. The IP1-1 cell (B, arrow) is visualized in a double flp-out clone that shows an additional weakly labeled cell body in the right hemisphere (arrowhead). The IP1-2 cell (F) is also visualized in a double flp-out clone together with the SP1-1 cell (see also Figure 6). The arrow marks the cell body of the IP1-2 cell that innervates the ipsi- and contralateral hemispheres by crossing the midline more dorsal (arrow) compared to the SP1-1 cell that crosses the midline next to the pharynx. The expression in the SOG belongs to third cell of a different type that does not innervate the brain hemispheres. Scale bars 25 µm.