Figure 6.

Progeny of c-Kit+ cells labeled at p2 continue to contribute to neuron production long term. (A) Quantification of XFP labeled cells from mice given a single dose of tamoxifen at p2 and killed at either p32 or p62 reveals increased c-Kit-derived cells at p62. Graphs show comparisons by total cells or by individual cell types. Note that neuronal counts indicate a significant increase at p62 versus p32 (t-test, P<0.01, n=5–6 mice per time point). Increased c-Kit-derived neuron label at longer survivals is consistent with ongoing c-Kit+ progenitor activity. (B) Both mature and new c-Kit-derived neurons are evident in olfactory epithelium from C-KitCre^ERT2/+; R26R-confetti mice treated with tamoxifen at p2 and killed at p62. RFP labeled neurons are evident in apical (mature) layers as well as basal (immature) layer (arrow). (C–E) Gap43 staining co-localizes with RFP+ immature neuron (arrow) in sections from c-KitCre^ERT2/+; R26R-confetti mice treated with tamoxifen on p2 and sacrificed p62. Older mature neurons are located more apically, in the Gap43 (−) layers. The presence of Gap43 (+)/XFP(+) neurons in this tissue reflects recent c-Kit+ neurogenesis. Nuclei are labeled with DAPI (blue). Dashed line marks basal lamina in (B–E); bar = 20 μm in (B–E).