FMRP_ CST7104 immunostaining in the mouse spiral ganglion (SG) during development. (a–c) CST7104 immunoreactivity at P7 in the apical (a) and basal (b) portions of the WT mouse and the basal portion of the Fmr1 KO mouse (c). (d–f) CST7104 immunoreactivity at P14 in the apical (d), middle (e), and basal (f) portions of the WT mouse. (g–i) CST7104 immunoreactivity at 3 months in the apical (d), middle (e), and basal (f) portions of the WT mouse. (j) Mean intensity of FMRP_CST7104 in the SG neurons. The number of neurons measured in each group is indicated in the corresponding bar. Data were analyzed by one-way ANOVA followed by Tukey’s multiple comparisons: F (2, 281) = 1155; p<0.0001. (k) FMRP immunostaining in the processes of SG neurons. Single focal plane of confocal image of double immunostaining of FMRP-CST7104 and Tuj1 in the SG of a 3-month-old WT mouse. Arrows point to the peripheral (p) and central (c) processes of a SG neuron. Scale bars = 10 μm in a, applies to a–I; 5 μm in k.