FIG. 4.
Analysis of Gfi1-Cre activities in hair cells of the inner ear. Gfi1Cre/+; R26R-lacZ inner ears were immunolabeled with antibodies against lacZ (green) and the hair cell-specific marker myosin-6 (MYO6, red). (a–d″) Immunolabeled cryosections at P0 show lacZ expression in the hair cells of cochlea (a–a″), saccule (b–b″), utricle (c–c″), and crista (d–d″). (e–e″) Whole-mount immunostaining of the Gfi1Cre/+; R26R-lacZ cochlea at P7 reveals the widespread expression of lacZ in cochlear hair cells. Asterisks in e″ indicate the hair cells positive for MYO6 but negative for lacZ. Abbreviations: OHC, outer hair cell; IHC, inner hair cell; WM, cochlear whole-mount immunostaining. Scale bars equal 10 μm in (a–a″), 50 μm in (b′–b″, c–c″), 30 μm in (d–d″), and 50 μm in (e–e″).