Fig. 3: Minor disruption of neuronal innervation pattern in HC-specific Emx2 KO.
From: Function of bidirectional sensitivity in the otolith organs established by transcription factor Emx2
a–b’ Hair bundle orientation across the LPR (yellow dotted line) of control (a, a’) is missing in the Emx2 cKO. Hair bundle orientation in the lateral region of Emx2 cKO utricles is similar to its medial region (b, b’, yellow arrows, n = 4) and is reversed from the lateral region of controls (a, a’, white arrows, n = 4). c, d Neuronal dye tracing from the cerebellum (green) and brainstem (magenta) are not well segregated in the Emx2 cKO utricles (d, n = 9) as in controls (c, n = 5). e Boxplot showing the quantification of the cb signal from the cerebellum over total signals from cerebellum and brainstem using z-stacks of confocal images in nine selected regions according to the “Methods” section. In control utricles, the relative cb signal is significantly higher in the lateral utricle (areas #1, 4, and 7) than the intermediate_medial (areas #2, 5, and 8) and the medial region (areas #3, 6, and 9) (Dunn’s pairwise tests, z = 3.83, p = 2.6E−04; z = 4.45, p = 2.5E−05). Similar decrease in relative cb signal was observed from lateral to intermediate-medial and the medial regions of Emx2 cKO utricles (Dunn’s pairwise tests, z = 3.57, p = 7.1E−04; z = 5.90, p = 1.1E−08). However, the relative cb signal in the intermed_medial region is higher in Emx2 cKO utricles, compared to control (Kruskal–Wallis H(1) = 9.82, p = 1.7E−03). Controls, n = 4; Gfi1Cre; Emx2F/−, n = 6. The two-sided Kruskal–Wallis rank-sum test and two-sided post hoc Dunn’s pairwise comparison tests were applied. In boxplots, boxes represent the interquartile range (IQR), and the thick lines inside show the median. Whiskers denote the lowest and highest values within 1.5 times the IQR. f Schematic summary of hair bundle orientation and afferent neuronal innervation pattern in control and Gfi1CreEmx2F/− (Emx2 cKO) utricles. Gfi1Cre; Emx2F/− utricles show uni-directional HCs and mild disruption of the neuronal innervation pattern, compared to controls. Scale bar = 100 μm in a–d; 25 μm in a’–b’. Source data are provided as a Source data file.
