REEPs Are Membrane Shaping Adapter Proteins That Modulate Specific G Protein-Coupled Receptor Trafficking by Affecting ER Cargo Capacity
Figure 4
Confocal REEP isoform co-localization.
HEK293A cells were transfected with HA-REEP1 (carboxyl terminus HA-epitope tag) and either Flag-REEP1, Flag-REEP2, or Flag–REEP6 (carboxyl terminus Flag-epitope tag) cDNA. Forty-eight hrs post-transfections, cells were fixed with 4% PFA, permeabilized, and examined by confocal microscopy. Flag-REEPs (Left) were identified by FITC-M2 (anti-Flag) antisera and HA-REEP1 (Middle) was labeled with Alexa 594 anti-HA antisera. Merged images are shown (Right). Co-expression of HA-REEP1 and Flag-REEP1 showed tremendous overlap, as expected. Flag-REEP2 and HA-REEP1 showed multiple punctate regions of co-expression. However, Flag-REEP2 also exhibited further extensions devoid of HA-REEP1 expression. Lastly, Flag-REEP6 and HA-REEP1 demonstrated a large degree of co-localization. Representative of three separate transfections. Scale bars: 25 µm.