| |
Fig. 1.
Spectrins αII and βII in the frog and mouse inner ear hair cells. (A–D) Frog (X. laevis). (A) Diagram of the amphibian inner ear, showing the sensory regions of the hearing organ (light green) and of the five balance end organs (dark green). (B and C) Side (B) and top (C) views of the utricular macula. (D) Isolated vestibular hair cells (VHCs). In frog hair cells, spectrins αII and βII are both detected in the cell apical region, specifically, in the cuticular plate (CP) and in the submembrane region of the apical junctional complex. In B and D, F-actin is stained in red by TRITC–phalloidin. (E–G) Mouse. (E) Diagram of the mammalian inner ear, showing the sensory epithelia of the hearing organ (cochlea) and of the five balance end organs. (F) Side views of the anterior crista. The VHCs can be identified by their myosin VIIa immunostaining. As in frog hair cells, spectrins αII and βII are detected mainly in the apical region of VHCs. (G) In isolated VHC and cochlear outer hair cell (OHC), spectrin αII (green) and spectrin βII (red) are both detected in the CP. In the OHC, spectrin αII is also present throughout the lateral wall. By contrast, the αII immunostaining of the VHC lateral wall does not cover the entire cell circumference (see diagrams). Bars, 5 µm. |
