Stereocilia Angle Quantification in Mouse Cochlea

The cochlea of the inner ear was isolated from mouse E18.5 embryos and attached to the transparent PET membrane of the cell culture insert (353096, Corning). They were then fixed with PBS containing 4% PFA for 1 h at room temperature, followed by three washes with PBS. Immunostained samples were visualized using a confocal microscope (LSM710; Zeiss, Oberkochen, Germany). The individual stereocilia angle was determined as previously described^{35 (link)}, and measured using the Fiji angle tool. Data for different genotypes was obtained from at least 100 cells in each hair cell row of mice from three different litters.