Figure 3.

Cochlear nuclei depend on Lmx1a/b, upstream of Gdf7, Atoh1, and Wnt3a (A). In the absence of Lmx1a/b neither cochlear hair cells, spiral ganglion neurons, nor cochlear nuclei develop (B). The choroid plexus is replaced by a roof plate that allows fibers to cross to the contralateral side (A,B). Cochlear nuclei are smaller in a conditional deletion of Atoh1 using Pax2-cre (C,D). In Atoh1-null mice, there is a normal central projection of SGNs without either peripheral hair cells or cochlear nuclei (E,F). Expression of Parvalbumin, Calbindin and Calretinin showing upregulation in the cochlear nuclei at the level of DCN and PVCN areas that increase in some but not all neurons (G). Modified after Idrizbegovic et al. (2006); Elliott et al. (2017); Elliott et al. (2021b); and Chizhikov et al. (2021). Scale bars: 100 μm (C–F). *** indicates significance.