Fig. 1. Localization of NOS in H. trivolvis embryos as revealed by NADPH-d staining. (A) Dorsal-anterior view of stage E25 embryo. NOS was expressed bilaterally in the dendritic knobs of ENC1 (arrows), the ciliary cells of the dorsolateral ciliary bands (arrowheads) and the protonephridia (n). The entire buccal mass (bu) was diffusely stained throughout, with greatest intensity occurring in the ciliated dorsal region. Staining also occurred in several unidentified cells near the embryonic surface (asterisks) that were widely spaced throughout the dorsal half of the embryo, including the region of the primordial mantle. The box outlines a deeper focal plane of the same embryo that was spliced in to reveal staining in dorsolateral ciliary cells (arrowheads) and the protonephridium on the right side. Scale bar, 40 µm. (B) Longitudinal profile of stage E35 embryo at the level of the left ENC1 (anterior at left). The dendritic knob (black arrow), apical dendrite (small black arrowhead), soma (white arrow) and proximal descending axon (white arrowhead) of ENC1 were all stained at this stage. In addition, intense staining occurred in a dorsolateral ciliary cell (upper black arrowhead), the dorsal buccal region (bu) and the protonephridium (lower black arrowhead). The diffusely stained radular sac (r) is also shown. Scale bar, 30 µm. (C,D) Summary diagrams of NAPHD-d staining in H. trivolvis embryos corresponding to the stages and orientations presented in A (C) and B (D). Only structures depicted in blue were stained. At stage E25 (C), only ENC1's dendritic knob was reliably stained (arrow), whereas by stage E35 (D), its apical dendrite, soma and proximal axon were also stained. At both stages, the dorsolateral cilia (dl), buccal region (bu), radular sac (r), protonephridia (n) and unidentified dorsal superficial cells (asterisks) were stained. Surprisingly, the ciliary cells comprising the pedal ciliary band (p) were not reliably stained at either stage.

Return to article