Figure 1. Depletion of primary cilia from mature dentate granule cells.
(a) Schematic diagram of the AAV injection in the dentate gyrus. (b) Representative confocal images of the hippocampus of IFT20 fl/fl mice transduced with AAV-CaMKII-eGFP or AAV-CaMKII-eGFP-Cre virus at 28 days post AAV labeling. Scale bar: 200 μm. (c) Representative confocal images of the granule cell layer of AAV-CaMKII-eGFP or AAV-CaMKII-eGFP-Cre 28 days post injection. Immunostaining with anti DCX (red) and ACIII (white) reveals that primary cilia were selectively ablated in mature DGCs by AAV-CaMKII-eGFP-Cre transduction, whereas no ciliary disruption was found by AAV-CaMKII-eGFP transduction. Scale bars: 30 μm (d) AAV-CaMKII-eGFP-Cre transduced cells exhibited a significantly depressed rate of ACIII expression versus AAV-CaMKII-eGFP controls. (Cre: 11.7 ± 2.1% ACIII+, eGFP: 82.6 ± 7.4% ACIII+; two-tailed un-paired t-test p = 8.5 × 10−7). (e) Cells in the granule cell layer that did not take up virus expressed primary cilia at comparable rates between eGFP control and Cre groups (CTRL: 82.6 ± 7.0%; Cre: 77.3 ± 7.2%; two-tailed unpaired t-test p = 0.634; n = 3,3). (f) Cre transduction resulted in significant gross depletion of primary cilia. (Averaged number of ACIII positive cells per field in CTRL and IFT20(−/−)mDGCs: 47.23 ± 2.78 for CTRL and 1.8 ± 0.28 for IFT20(−/−)mDGCs; p = 5.985 × 10−15; n = 4,4). (g) Expression of ACIII in DCX+ cells did not differ significantly between eGFP-Cre and eGFP controls (CTRL: 9.5 ± 3.6% co-localization; IFT20(−/−)mDGCs : 12.8 ± 2.9% co-localization; two-tailed unpaired t-test p = 0.50). Fields size: 320 μm × 320 μm × 36 μm. ***p < 0.001; ****p < 0.0001; n is the number of animals.