Neuronal deletion of Amot affects cerebellar morphology.

(A) Strategy for the generation of Amot conditional knockout mice, showing the Amot flox allele (upper diagram) and recombined allele after Cre-mediated excision (lower diagram). (B) Lower Amot expression in the cerebellum of Amot fl/fl;Syn-Cre P30 mice, analyzed by western blot. (C) Amot fl/fl;Syn-Cre mice exhibited a smaller cerebellum compared with control Amot fl/fl littermates. (D) Quantitative analysis of cerebellar weight in Amot fl/fl (n = 9) and sex-matched Amot fl/fl;Syn-Cre (n = 6) mice on P30. p = 0.0411. The measurements were normalized to the whole-brain weight. (E) Sagittal cerebellar sections of Amot fl/fl and Amot fl/fl;Syn-Cre P30 mice that were immunolabeled for calbindin (green) to visualize Purkinje cells and the molecular layer and NeuN (red) to visualize the granule cell layer. Numbers indicate individual lobes. (F) Quantification of Purkinje cell number in sagittal sections of Amot fl/fl mice (n = 3 mice and at least three sections per mouse) and Amot fl/fl;Syn-Cre mice (n = 4 mice and at least three sections per mouse). p = 0.5405. (G) Decrease in molecular layer thickness in Amot fl/fl;Syn-Cre mice, visualized by anti-calbindin antibody; lobe III down the preculminate fissure. (H-J) Thickness of the molecular (H), granular (I), and Purkinje (J) cell layers in the cerebellum of Amot fl/fl mice (n = 3 mice and at least three sections per mouse) and Amot fl/fl;Syn-Cre mice (n = 5 mice and at least three sections per mouse) on P30 measured in lobe III down the preculminate fissure. p = 0.0135, p = 0.4169, and p = 0.4615. (K, L) Granule cell distribution (K) and quantification (L) in the molecular layer of the cerebellum in P30 Amot fl/fl mice (n = 3 mice and at least three sections per mouse) and Amot fl/fl;Syn-Cre mice (n = 5 mice and at least three sections per mouse), shown as a percentage of NeuN-positive cells per 20,000 μm². p = 0.7333. Numerical values that underlie the graphs are shown in S1 Data. Statistical significance was analyzed using two-tailed unpaired t test. *p < 0.05. Bars represent the mean ± SD. Scale bars = 5 mm in C, 1,000 μm in E and 20 μm in G and K. Amot, angiomotin; ns, not significant; P, postnatal day; SD, standard deviation.