Figure 7: Regulation of surface GABAA receptors by GSK3b activation.
From: Activity-dependent regulation of dendritic growth and maintenance by glycogen synthase kinase 3β
(a,b) Representative images show surface GABAARs by γ2 staining (a) and AMPARs by GluA1 labelling (b) on dendrites of neurons expressing EGFP (Ctrl), GSK3β-S9A (+S9A) and GID5-6 (+GID5-6) at DIV16 (+3 d after transfection). Dendritic regions enclosed by the white rectangles in the top panels are shown in magnified views below. For each cell, three high magnification panels are shown: colour merged (green: EGFP, red: surface receptors), EGFP with yellow outline of the dendritic segment, and surface GABAA receptors with regions outside of dendritic segment masked using EGFP fluorescence. Scale bar in top panels, 20 μm, lower panels, 5 μm. (c,d) Bar graphs show changes in density and size of surface GABAAR puncta normalized to the EGFP group (Ctrl). (e,f) Bar graphs show the normalized changes in density and size of AMPAR puncta. (g) Representative images show the co-localization of EGFP-gephyrin clusters with surface GABAARs. Magnified panels are shown below. Scale bars are 20 μm and 5 μm for the top and bottom panels, respectively. (h) Bar graph depicts incidents of co-localization between EGFP-gephyrin (EGFP-G) and surface GABAARs. The first bar indicates the percentage of EGFP-G puncta colocalized with GABAAR clusters, and the second represents the percentage of GABAAR clusters localized with EGFP-G puncta on the same branch. (i,j) Bar graphs depict the changes in density and size of EGFP-gephyrin puncta in dendrites at DIV16 (+3 after transfection). Numbers indicate the total number of cells examined for each group (from at least three independent batches of culture). Error bars: s.e.m. *P<0.05 compared with EGFP-G (Ctrl) by Student’s t-test.
