Prickle1 mutation impairs type II fiber outgrowth.

<p>(A-B”‘) The outgrowth of type II SGN afferents was analyzed by immunocytochemistry in <i>Prickle1C251X</i> mutants at P0. Cochleae were immuno-labeled with antibodies against β-tubulin. Overview of the <i>Prickle1</i>^<i>+/+</i> (A) and <i>Prickle1</i>^{<i>C251X/C251X</i>} (B) cochleae, and the type II afferents from the corresponding basal (A’ and B’), middle (A” and B”), and apical (A”’ and B”’) turns are shown. (C-D”) The outgrowth of type II SGN afferents analyzed by immunocytochemistry in <i>Prickle1</i>^<i>f/f</i><i>; Pax2-cre</i> mice. Cochleae were immune-labeled with antibodies against Myo7a and β-tubulin, and the outgrowth of type II SGN afferents are shown in control mice (C-C”) and in <i>Prickle1</i>^<i>f/f</i><i>; Pax2-cre</i> mutants (D-D”) at P33. Arrow, type II afferents turning towards the apex; filled triangle, type II afferents still developing; empty triangle, fibers that grew past the outer hair cells. Scale bar, 100 μm.