Figure 5.
Phosphomimetic mutation of α2 Ser-359 reduces binding to gephyrin (Gphn) and collybistin (Cb) in vitro. A, schematic illustrating a small section of the large intracellular loop of the GABAAR α2 subunit. The gephyrin- and collybistin-binding sites are shown, and the Ser-359 phosphorylation site is depicted in blue. B and C, detergent-solubilized cortical neuronal lysates were incubated with GST alone, GST-α2 WT, S359A phosphonull, or S359D phosphomimetic mutants. Bound proteins including gephyrin and collybistin were detected by immunoblotting. The bottom panels show Ponceau staining illustrating the amounts of GST utilized. Right, graphs show quantification of immunoblots. *, p < 0.05; ****, p < 0.0001; one-way ANOVA with Tukey's post hoc test, n = 5. Data are means ± S.E. (error bars).