Mouse Model Characterization for Cochlear Studies

The following mouse strains were used: Lgr5^{DTR-EGFP /+} (gift from F. de Sauvage, Genentech) [16 (link)], Atoh1-mCherry (gift from N. Segil, Univ. Southern Calif.), Pax2-Cre (gift from A. Groves, Baylor College of Medicine) [29 (link)], Rosa26^GCaMP3/+ (known as Ai38, Stock #14538, Jackson Laboratory) [67 (link)], GLAST^CreERT/+ (known as Slc1a3-CreERT, Stock #12586, Jackson Laboratory) [28 (link)], Sox2^CreERT2/+ (Stock #17593, Jackson Laboratory) [68 (link)], Rpl22^HA/+ (Stock #11029, Jackson Laboratory) [38 (link)], Plp1^CreERT/+ (Stock #5975, Jackson Laboratory) [25 (link)], Rosa26R^tdTomato/+ (known as Ai14, Stock #7914, Jackson Laboratory) [27 (link)], and Rosa26R^DTA/+ mice [26 (link)]. Mice of both genders were used. To ablate cochlear SCs in Lgr5^DTR/+ mice, diphtheria toxin (0.1 to 4 ng/g, IM or IP, Millipore) was administrated at P1. Saline (0.9% NaCl) treated Lgr5^{DTR /+} mice and diphtheria toxin–treated wild-type mice were used as controls.
To activate Cre recombinase, tamoxifen dissolved in corn oil (0.075 mg/g for Plp1^CreERT/+ mice and 0.2 mg/g for GLAST^CreERT/+ mice, IP, Sigma) was administered at P0 to P1. EdU (25 μg/g, IP, Invitrogen) was injected to label proliferative cells. Institutional Animal Care and Use Committee of Stanford University School of Medicine approved all procEdUres in accordance with NIH guidelines (protocol #18606).