Q124R substitution decreases heterodimerization with mGlu2 and mGlu7. (A) Schematic representing the “bait” and “prey” method to measure mGlu dimerization propensity. HA or MYC signal are measured in separate wells and normalized to DRAQ5 cell stain to account for cell number. (B) Western blot analysis of truncated, nonedited, and edited mGlu4 receptor constructs from concentrated media or whole-cell lysates. (C) mGlu4 dimerization propensity assessed by the ratio of the secretable mGlu4 (MYC) signal to full length (HA) signal. Data are normalized to the dimerization levels of nonedited mGlu4. Mean ± S.E.M. Significance assessed by paired t-test. (*) P ≤ 0.05. (D) Replot of the data in C after pooling data for receptors where editing did not affect dimerization showing the order of mGlu4 dimerization propensity. Mean ± S.E.M. Significance assessed by ANOVA with Dunnett's post hoc. (ns, P > 0.05; [*] P ≤ 0.05; [**] P ≤ 0.01; [***] P ≤ 0.001; [****] P ≤ 0.0001).
