Cochlear expression of genes in the headbobber deletion on Chr7.

<p><b>A–B:</b> Immunohistochemistry on ear sections at postnatal day five shows Gpr26 expression in spiral ligament fibrocytes (black arrowheads in A). We did not detect presence of Gpr26 in <i>hb/hb</i> cochleae at this stage (B). Scale bar: 10 µm. <b>C–D:</b> Immunohistochemistry on ear sections at postnatal day five shows Cpmx2 expression specifically in intermediate cells of stria vascularis (arrowheads in C). No protein was detected in <i>hb/hb</i> (B). Scale bars: 10 µm. <b>E–H:</b> Immunohistochemistry for Chst15 in <i>hb/hb</i> and control littermates at P5. At this stage, Chst15 shows expression in hair cells (arrowheads in E), marginal cells (black arrowheads in G) and their interdigitation to intermediate cells of stria vascularis (red arrowheads in G). As shown in F and H, we cannot detect any significant expression of Chst15 in <i>hb/hb</i> compared to littermate controls in the organ of Corti (F) and stria vascularis (H), although we can still detect a few protein dots (black arrowheads in F,H), which can either be an artifact or due to non-specific staining. Scale bar: 10 µm. <b>I–J:</b> Whole mount immunofluorescence of organ of Corti at postnatal day five shows expression of Chst15 (green) in the basal region of stereocilia of both inner and outer hair cells (arrows in I). We do not detect any Chst15 expression in the <i>hb/hb</i> disorganized hair bundles (arrowheads in J). Phalloidin (red) stains actin filaments of stereocilia. Scale bars: 10 µm. ohc: outer hair cells; ihc: inner hair cells.