Loss of Fbx2 causes membrane abnormalities in support cells of the cochlea. a, b, TEM analysis of cochlea from 2-month-old (2 mo; a) and 3.5-month-old (3.5 mo; b) WT and KO mice showing disruption of support cell (Claudius' cells) membrane integrity (black arrows). Inset photo, An asymmetric, juxtamembranous accumulation of membranous structures is present in support cells of Fbxo2−/− mice at 3.5 months. Scale bars: 2 μm; insets, 1 μm.