Alpha-fodrin (brain spectrin) immunocytochemical localization in rat vestibular hair cells

The presence of a spectrin-related protein in rat vestibular sensory receptors was demonstrated by immunocytochemistry and immunoblotting using affinity purified anti alpha-fodrin antibodies. Intense immunoreactivity was found in the apical pole of sensory hair cells where it seems to be concentrated in the cuticular plate. In contrast, alpha-fodrin immunoreactivity was absent from the stereocilia. We suggest that a spectrin-related protein participates in the organization of the cuticular plate of vestibular hair cells by cross-linking actin filaments as well as by anchoring the cuticular plate to the apical cell membrane.