Figure 14.

Localization of ArPPLN1b immunoreactivity in the terminal tentacle and associated structures in the arm tip of A. rubens. (a) Immunostaining in a transverse section of a terminal tentacle and in the surrounding body wall epithelium. The boxed regions are shown at higher magnification in panel (b) and (c). (b) A high magnification image of arm tip body wall epithelium showing immunostained bipolar shaped cells (arrowhead) and in a dense meshwork of fibers in the underlying basiepithelial nerve plexus (asterisks). (c) High magnification image of the terminal tentacle showing immunostained bipolar shaped cells in the epithelium (arrowheads) and in a dense meshwork of fibers in the underlying basiepithelial nerve plexus (asterisks). (d) Immunostaining in a transverse section at the base of the terminal tentacle. Immunostained cells and processes can be seen here in the body wall epithelium, the terminal tentacle and associated lateral lappets and the optic cushion. Abbreviations: CuL, cuticle layer; Ep, epithelium; LL, lateral lappet; OC, optic cushion; TT, terminal tentacle. Scale bars: 50 μm in (a); 10 μm in (b), (c); 100 μm in (d)