Fig 4. Mutating the CD4 TMD GGxxG motif does not impair dimerization at steady-state.

(A) Grey-scale images of mCherry (top) and GFP (bottom) intensities pre and post mCherry ablation for representative cells. (B) Plot of relative mCherry values pre- and post-ablation for all cells analyzed. The average ablation of all populations was below 10% and did not differ significantly from each other. (C) FRET_E values for CD28^GFP/Ch, PD1^GFP/Ch and CD4T^GFP/Ch cells. Representative of two experiments with independently generated cell lines. (D) FRET_E values for CD4WT^GFP/Ch vs. CD4T^GFP/Ch cells. Concatenated data from two independently generated cells lines is shown because the CD4WT^GFP/Ch cells had a broader range of donor and acceptor levels that limited the number of cells available for subset analysis (methods). (E) FRET_E values for CD4T^GFP/Ch vs. CD4T^TMD-GFP/Ch cells. Representative of two experiments with independently generated cell lines. Matched expression for analysis was based on median pre-bleach intensity. Dots represent single cells and green bars represent median values (*p<0.05, **p<0.001; ***p<0.0001; Mann-Whitney).