Figure 1. Gfi1^Cre mediated non-HC recombination.

(A) Schematic of the auditory and vestibular epithelia showing a heterogeneous cellular population made up of hair cells (HCs), epithelial non-HCs, non-epithelial cells and neurons. (B) Whole mount immunofluorescence of an apical turn from a P1 Gfi1^Cre/+;ROSA26^CAG-tdTomato mouse cochlea showing extensive non-HC recombination as a result of Gfi1^Cre. (C) Cochlear whole mount immunofluorescence of a P1 Gfi1^+/+;ROSA26^CAG-tdTomato littermate showing no recombination in any cells in the absence of Cre recombinase (n = 3). Whole mount (D–F,H–J) (n = 5) and section (G,K) (n = 3) immunohistochemistry showing the presence of non-HC Gfi1^Cre mediated tdTomato expressing cells (white arrowheads) in the basal, middle and apical turns of the cochlea (D–F), and utricle, saccule and crista vestibular organs (H–J). HCs are denoted by white arrows, scale bars = 100 μm.