Fig. 8.

Immunohistochemical localization of yotiao in rat skeletal muscle. Yotiao is predominantly localized subjacent to AChRs in the NMJ and demonstrates a staining pattern similar to the intermediate filament desmin. Yotiao was labeled by B5843 followed by Texas Red-conjugated secondary antibody (A,B; red) or BODIPY-conjugated secondary antibody (C; green). AChR was labeled with biotinylated α-bungarotoxin followed by BODIPY-conjugated streptavidin (A, B;green). Desmin was labeled with mAb 1403 followed by Texas Red-conjugated secondary antibody (C;red). A, Large-field view showing yotiao expression at every NMJ. The sarcolemma is stained only in the perijunctional region but not beyond. B, High-magnification view of the NMJ reveals yotiao staining subjacent to AChR staining. Arrowheads indicate Z lines weakly stained for yotiao. C, Similar pattern of yotiao and desmin localization in the subsynaptic region. However, note absence of yotiao staining, but presence of desmin staining, on the general sarcolemma. As is common with transverse sections, distinct Z lines are not apparent in this view, but Z-line staining by mAb 1403 has been documented (Sealock et al., 1989). Scale bar: A, 25 μm; B, 5 μm; C, 10 μm.