Sox2creert2

All procedures were approved by the UCSF Institutional Animal Care and Use Committee (IACUC) and were adherent to the NIH Guide for the Care and Use of Laboratory Animals. Mouse alleles used in this study were provided by The Jackson Laboratory and include Sox2^eGFP (Arnold et al, 2011), Sox2^CreERT2 (Smith et al, 2009), Sox2^fl/fl (Taranova et al, 2006), Rosa26^mTmG (Muzumdar et al, 2007), Rosa26^DTA (Wu et al, 2006), and Kit^CreERT2 (Klein et al, 2013).

All procedures were approved by the UCSF Institutional Animal Care and Use Committee (IACUC). Mouse alleles used in this study were provided by The Jackson Laboratory and include: Phox2b^LacZ/LacZ (RRID:MGI:2172761) (Pattyn et al., 1999 (link)), Krt14^CreERT2 (RRID:MGI:5435569) (Vasioukhin et al., 1999 (link)), Sox2^CreERT2 (RRID:MIG:5512893) (Andoniadou et al., 2013 (link)), Sox2^fl/fl (RRID:MIG:4366456) (Smith et al., 2009 (link)) and Rosa26^mTmG (RRID:MIG:3623345) (Muzumdar et al., 2007 (link)). Sample size was calculated using the Resource Calculator (Mead, 1988 ).

OF1 and C57/B6J2 mice were obtained from Charles River Breeding Laboratories. Prdm1MEGFP transgenic mice were kindly provided by Mitinori Saitou; Lef1tm1 Rug mice were provided by Rudolf Grosschedl and Werner Held. Sox2Cre, Sox2CreERT2, Prdm1Cre, Wnt1Cre, Prdm1 CA, and ROSAYFP mice were obtained from the Jackson Laboratory (Bar Harbor, United States) (Table 1). The strains carrying the Cre recombinase and ROSAYFP were kept in heterozygosity, while the conditional knockout was performed in homozygosity. Genotyping was conducted using the primers listed in Table 2. All animals were maintained in a 12 h light cycle providing food and water ad libitum. Mice were sacrificed by intra-peritoneal (i.p.) injection of pentobarbital. Experiments were conducted in accordance with the EU Directive (86/609/EEC) for the care and use of laboratory animals and that of the Swiss Confederation. Mating of adult female and male mice was carried out overnight. Time-pregnant mice were sacrificed by injection of pentobarbital and uteri with embryos were removed by dissection.

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).