Basilar papillae were cultured with streptomycin for 48 hours following transfection with either a non-targeting miRNA (A–D) or anti-miR181a (E–H). Whole-mounts were then labeled for the hair cell marker myosin VI, sterocilia bundle component actin, and the early cell death marker caspase-3. Hair cells were completely eliminated from the high frequency segment of basilar papillae exposed to streptomycin, regardless of transfection with anti-miR181a (A, B, E, F). Further, streptomycin exposure triggers extensive cell death with or without anti-miR181a transfection (C, G). In contrast, epithelia transfected with a non-targeting miRNA and unexposed to streptomycin retain hair cells (I, J) and do not show extensive apoptosis (K). The neural edge is to the right of each panel, and the proximal segment is to the top. The arrow in panel D shows what are likely homogene cells remaining after microdissection. The scale bar in A also applies to B-L.