Functional Characterization of a Novel Family of Acetylcholine-Gated Chloride Channels in Schistosoma mansoni
Figure 5
Immunolocalization of SmACC-1 and SmACC-2 in Schistosoma mansoni.
Adult and 6-day old schistosomula were fixed and incubated with affinity-purified anti-SmACC-1 or anti-SmACC-2, followed by Alexa 488-conjugated secondary antibody (green). In some animals the body wall musculature was counterstained with tetramethylrhodamine B isothiocyanate (TRITC)-labeled phalloidin (red). (A) A Z-projection of SmACC-1 immunoreactivity in an adult male worm. SmACC-1 is present in both the oral sucker (os) and in minor nerve fibers of the peripheral innervation of the worm's body wall. The nerve fibers are varicose in appearance, resembling beads on a string (enlarged region, solid arrows) and are repeated along the length of the body. The asterisk (*) indicates an area of non-specific fluorescence resulting from tissue damage (B) Z-projection of an adult male worm labeled with anti-SmACC-2 (green) and phalloidin (red). SmACC-2 immunoreactivity is present in varicose nerve fibers (solid arrows) that cross the body in a mesh-like pattern indicative of PNS staining. SmACC-2 and the phalloidin –stained body wall musculature are present at different depths of the animal, suggesting that SmACC-2 does not directly innervate muscle. (C) Tubercles (tb) of an adult male worm labeled with anti-SmACC-2 and phalloidin. Specific, punctate SmACC-2 immunoreactivity can be seen along the surface and within the tubercles (arrows). (D) SmACC-2 forms a pattern of concentric, varicose nerve fibers that run the entire length of a 6-day old schistosomulum. A similar expression pattern was observed in schistosomula labeled with anti-SmACC-1 antibody (not shown). (E) Transmitted light and corresponding fluorescent image of a negative control worm labeled with peptide-preadsorbed anti-SmACC-1 and (F) the same negative control for peptide-preadsorbed anti-SmACC-2. The scale bars for the two negative controls are 50 µm (panel E) and 20 µm (panel F).