Skip to main content
. 2020 Apr 1;40(14):2808–2816. doi: 10.1523/JNEUROSCI.2654-19.2020

Figure 4.

Figure 4.

PP2A binding to GABABR1 modulates the level of phosphorylation at S783 in GABABR2 subunit. A, Coimmunoprecipitation (co-IP) of GABABR1 and PP2A from cultured rat neurons treated with membrane permeant TAT-R1-pep or TAT-scrambled peptides. Total lysates (input) shown on the left. Note decrease in PP2A B55 and C subunits with TAT-R1-pep. Bar graph shows the quantification of co-IP (PP2A-B55/R1 ratio) for TAT-R1-pep condition normalized to the TAT-scrambled peptide. Note significant decrease in PP2A with TAT-R1-pep. Mean ± SEM shown with individual points (*p = 0.0122; t = 4.214, df = 3; one-tailed ratio paired t test). Asterisk for IgG control indicates nonspecific signal with secondary antibody. Arrowhead indicates size for GABABR1. B, Increase in phosphorylation of S783 in GABABR2 subunit after TAT-R1-pep treatment. Blot shows Western with antibody recognizing phosphorylated S783 in R2 (p-S783) for scrambled (TAT-scramb) and TAT-R1-pep conditions following immunoprecipitation of the R1 subunit. Ponceau S shows total protein after IP. C, Bar graph shows the quantification of p-S783 phosphorylation for the TAT-R1-pep condition normalized to the TAT-scrambled peptide. Note significant increase in phosphorylation with TAT-R1-pep (*p = 0.0266; t = 4.157, df = 2, one-tailed ratio paired t test).