The stereocilia of <i>Diap3</i>-overexpressing mice become progressively abnormal from 4 to 24 weeks of age.

<p>Cochlear whole mounts from wild-type (A), 771 (B), and 924 (C) mice at 4, 8, 16, and 24 weeks of age were incubated with fluorophore-conjugated phalloidin to label the F-actin core of stereocilia. Scale bar represents 10 µm. (A) IHC stereocilia from wild-type mice appeared to be uniform in length and diameter, with slight disorganization as a result of the fixation and mounting procedures. At 4 weeks of age, the stereocilia of line 771 (B, top panel) appear sparse and variable in length, while those of line 924 (C, top panel) appear similar to those of wild-type mice (A, top panel). In both transgenic lines, some of the stereocilia appear to collapse against each other at age 8 weeks (B and C, second panels), and appear elongated by 16 weeks of age (B and C, third panels). By 24 weeks (B and C, bottom panels), stereocilia of both lines appear even longer, with a reduction in the number of stereocilia per IHC compared to wild-type mice (A, bottom panel).