Figure 7. The stereociliary bundles of the HCs in the Rfx1/3cKO mice are properly polarized.

(a) Representative confocal microscopy images from the basal, middle and apical turns of 3-day-old Rfx1/3 cKO mice (n=3) and their wild-type littermate controls (n=3). Cochleae were stained with phalloidin (green) to define the actin cytoskeleton and stereociliary bundles, and an antibody for acetylated tubulin (red) to define the kinocilium. The stereociliary bundles of the wild-type and mutant mice appear properly polarized in the basal and middle turns. In the apical turn at P3, the polarity of the bundles is less organized in both the wild-type and mutant mice. Scale bar, 5 μm. (b) Quantification of the angle of deviation of the bundles in the wild-type and mutant mice, as measured from a line perpendicular to the axis of the pillar cells, crossing through the middle of the HCs. Results from the basal and middle turns are represented in a scatter dot plot. Each dot represents a HC, horizontal bars represent the median value. The polarity of five consecutive IHCs, first row OHCs, second row OHCs and third row OHCs was measured from cochleae of three separate mice from each genotype and from two regions: basal and middle turns, separately. A one-way ANOVA followed by a Tukey’s test was used to compare the results. No statistical significant differences were detected (P value>0.05).