Fig. 5.
Loss of LIN28A/B inhibits supporting cell-to-hair cell conversion in response to Notch inhibition. (A) Experimental strategy. Cochlear explants from stage P2 UBC-CreERT2;Lin28af/f;Lin28bf/f mice and Lin28af/f;Lin28bf/f littermates were cultured in the presence of 4-hydroxy-tamoxifen (TM) or DMSO (vehicle control). At day 1 of culture, cochlear explants received Notch inhibitor LY411575 and 3 d later cochlear explants were analyzed for new hair cells. (B) Confocal images of midapical turn of control (TM: Lin28af/f;Lin28bf/f; DMSO: UBC-CreERT2;Lin28af/f;Lin28bf/f; DMSO: Lin28af/f;Lin28bf/f) and Lin28a/b dKO cochlear explants (TM: UBC-CreERT2;Lin28af/f;Lin28bf/f) immuno-stained for MYO7A (magenta) and SOX2 (green). (C) Quantification of total number of hair cells (MYO7A+) as well as newly formed hair cells (MYO7A+ SOX2+) for control (blue, red, green) and Lin28a/b dKO (black) in B. Graphed are individual data points, representing average values per animal, and mean ± SD for control (blue, red, green) and Lin28a/b dKO (black), n = 6 animals per group, two independent experiments. Two-way ANOVA with Tukey’s correction was used to calculate P values.