Figure 2.
Interaction between PP2A and GABABR full-length proteins as detected by proximity ligation assay (PLA) in HEK293 cells. Ai, Schematic of the PLA reaction between PP2A (antibody against C subunit) and eYFP-tagged GABABR (antibody against GABABR1 C terminus). Aii–Avi, Representative PLA images of HEK293 cells for the indicated experimental conditions: HEK293 cells were transfected with the cDNAs indicated above each image, and primary antibodies used for PLA are indicated (bottom left). Green: eYFP signal indicating transfected cells. Red is the PLA signal; each red puncta represents a single PP2A-GABABR complex. Blue is DAPI staining. B, Scatter plot shows quantification of PLA signal from one representative experiment. Each data point represents analysis of one image containing 1–11 HEK cells. Presence or absence of primary antibodies and secondary probes (m, mouse; r, rabbit) are indicated below. Magenta bar indicates mean. ****p < 0.0001, one-way ANOVA with Tukey's post hoc test (F(5,53) = 70.76). C, Scatter plot of normalized PLA signal pooled from three independent experiments. Data points were normalized to the R1 + R2 + GIRK2a PLA condition (first column). UT, Untransfected. Magenta bar indicates mean (****p < 0.0001, one-way ANOVA with Tukey's post hoc test; F(6,182) = 134.5).