Cilia are absent in mature GC neurons despite docking of mother centrioles at cell surface. (A) Sagittal cerebella sections from a P25 mouse were immunostained with antibodies to ARL13B (magenta) to visualize cilia, P27KIP1 (yellow) to mark GC neurons, SOX9 (cyan) to mark glial cells, and counterstained with DAPI (blue) before imaging with widefield microscopy. Cilia are prominent in SOX9 glial cells; however, they are not detected on P27KIP positive GC neurons. Scale bar: 10 μm. (B) Enlarged view of granule cells and a glial cell from the IGL of A. (C and D) Cilia frequency (C) and length (D) were measured in immunostained images acquired with widefield microscopy. Average frequencies of three sections each, from three animals is shown in C and individual cilia measurements from the same sections are shown as small symbols in D with the average per animal represented by the large symbol. The line and error bars represent the mean and standard deviation of the individual animal averages. (E) EM image from a serial-section transmission EM volume of the IGL of an adult mouse cerebellum. Centrioles are indicated with yellow arrowheads. Scale bar: 1 μm. (F) The percentage of GCs in the adult IGL with centrioles in each classification are quantified. (G) Serial sections of the centriole highlighted in E. Scale bar: 200 nm.
