Figure 1.

Tectorial membrane abnormalities in Pit1^dw mice. A, Plastic sections of the organ of Corti taken from wild-type and Pit1^dw mutant mice at P12 and P21 were visualized by light microscopy. The arrow indicates the unopened tunnel of Corti (TC) in the P12 old mutant. OHCs, IHCs, and pillar cells (PC) are indicated. Scale bars: 10 μm. B, Analysis of TECTB content in the tectorial membrane of P21 animals using Western blotting. Two polypeptide bands of TECTB are present at ∼43 and 47 kDa. The blot was reprobed with a GAPDH antibody, and equivalent amounts of immunoreactive ∼36 kDa protein were detected, indicating equivalent amounts of proteins were loaded (data not shown). C, Transmission electron micrographs illustrate the ultrastructure of the tectorial membrane in P42 old animals. Regions shown are from the central core of the tectorial membrane overlying the organ of Corti. Fine diameter filaments (arrows) forming the striated sheet matrix are different in the wild-type mice and the mutants. Scale bars: 2 μm.