Figure 3.

Expression Profiling of DIABLO in the Developing Human and Mouse Inner Ear

(A) Expression of DIABLO transcript in different human embryonic tissues at week 17 of pregnancy was evaluated by real-time quantitative RT-PCR. Data are means ± SD of three independent experiments.

(B) Schematic representation of the Corti's organ in the inner ear. The sensory epithelium of the cochlea consists of inner and outer hair cells. Supporting cells of the Corti's organ include Hensen's, Claudius's, Deiter's, and Boettcher's cells.

(C) Production of DIABLO in the developing mouse cochlea. (I) Cytoplasmic distribution of DIABLO was weakly detected ubiquitously in developing cochlea, including the nascent inner hair cell (IHC) at the base, at E15.5. (II) By E18.5, DIABLO production was significantly elevated in both inner and outer hair cells (IHCs and OHCs), in particular in the cytoplasm above the nuclei. DIABLO was also readily detected in other cell types, including the greater epithelial ridge (GER). (III) DIABLO production was persistently higher in cochlear hair cells at P0 than in surrounding cells. More than three OHCs were present in the image because of the section angle. (IV) By P6, DIABLO was downregulated to a level that was indistinguishable from that of the GER. Myo7a: myosin VIIa that labels hair cells. Magnification: 40×.