Fig. 6

Interneuron-specific transduction in the cerebellar cortex by the mGAD65 promoter. VGAT-tdTomato mice received intravenous infusions of AAV-PHP.B expressing GFP under the control of the mGAD65 promoter or mDlx enhancer. Three weeks after the viral injection, cerebellar sections were immunostained for calbindin, a marker for Purkinje cells. a, b Representative fluorescent images of the cerebellar cortex (lobule 8) [GFP (left), tdTomato (middle), and the merged images with calbindin (blue) (right)]. Scale bars; 50 μm. c Graphs showing percentage of GFP ( +) cells in tdTomato ( +) cells in the molecular layer (ML) and granule cell layer (GCL). For the mGAD65 promoter, 551 tdTomato ( +) cells in the molecular layer were examined, in which 443 cells expressed GFP; in the granule cell layer, 546 tdTomato ( +) cells were observed, in which 44 cells expressed GFP (n = 6 sections from 6 mice). For the mDlx enhancer, 1061 tdTomato ( +) cells in the molecular layer were examined, in which 2 cells expressed GFP; in the granule cell layer, 495 tdTomato ( +) cells were observed, in which 4 cells expressed GFP (n = 5 sections from 5 animals). d Graph showing ratio of GFP ( +) Purkinje to total Purkinje cells. For the assessment of the mGAD65 promoter, we examined 1622 Purkinje cells immunolabeled for calbindin from 4 mice, in which only 15 cells expressed GFP. Similarly, for the mDlx enhancer, we observed 1451 Purkinje cells from 4 mice, and we found 6 GFP ( +) cells