Skip to main content
. 2012 Nov 29;22(5):890–903. doi: 10.1093/hmg/dds495

Figure 7.

Figure 7.

VGLUT2 immuno-analysis reveals normal CF–PC synapse distributions in PrP-floxed-SCA7-92Q BAC mice subjected to ataxin-7-92Q transgene suppression. (A–F) We immunostained sagittal cerebellar sections for calbindin (red) and for VGLUT2 (green), a marker of CF–PC synapses. VGLUT2-positive puncta are evenly distributed throughout the cerebellar molecular layer in (A) non-transgenic and (B) PrP-floxed-SCA7-92Q BAC mice at 20 weeks of age. Normal distributions of VGLUT2 puncta were also noted in (C) 40-week-old non-transgenic control mice; however, in (D) 40-week-old PrP-floxed-SCA7-92Q BAC mice, the VGLUT2-labeled CF–PC synapses aggregate proximal to PC bodies and are no longer evenly distributed. (E) VGLUT2 distribution in 43-week-old oil-treated bigenic mice was abnormal, while (F) tamoxifen-treated bigenic mice exhibited CF–PC synapses with more normally distributed VGLUT2 immunostaining. Scale bar, 20 µm. (G) To measure the volume of VGLUT2 immunostaining in each 3-D image, a line was drawn from the PC layer to the pial surface (white line). A second intersecting line (white) was drawn perpendicular to the first line at the midpoint of the molecular layer to divide the proximal region from the distal region. The volume for total VGLUT2 CF–PC synapse immunolabeling was then calculated for the distal and proximal regions (colored boxes). (H) At 20 weeks of age, the distribution of VGLUT2-positive CF–PC synapses in the molecular layer is similar in non-transgenic and PrP-floxed-SCA7-92Q BAC mice (n = 6–7/group). (I) At 40 weeks of age, the distribution of CF–PC synapses is significantly altered with increased VGLUT2 staining observed in the proximal region and lessVGLUT2 staining present in the distal region for PrP-floxed-SCA7-92Q BAC mice compared with non-transgenic mice (P < 0.01, two-tailed t-test, unpaired; n = 6/group). (J) Tamoxifen-treated bigenic mice, however, display a significantly improved VGLUT2 staining distribution at CF–PC synapses, when compared with oil-treated bigenic mice (P < 0.05, two-tailed t-test, unpaired; n = 6/group). Error bars = SEM.