REEPs Are Membrane Shaping Adapter Proteins That Modulate Specific G Protein-Coupled Receptor Trafficking by Affecting ER Cargo Capacity
Figure 2
Confocal intracellular immunolocalization of REEPs.
HEK293A cells were transfected with Flag-REEP1, -REEP2, or -REEP6. Forty-eight hrs post-transfection, cells were fixed with 4% PFA, permeabilized, and examined by confocal microscopy. REEPs were stained with M2 antibody (anti-Flag). Golgi and ER compartments were stained for giantin and calreticulin expression respectively. A: REEP1/2/6 (Left) did not co-localize with the Golgi compartment, delineated by the Golgi marker giantin (Middle), as seen in merged images (Right). B: REEP1/2/6 staining (Left) delineated an intracellular reticular pattern that overlapped with the ER marker calreticulin (Middle), as seen in merged images (Right). All REEPs studied identified a reticular pattern more diffuse than that labeled by anti-calreticulin antisera, suggesting a possible alteration in calreticulin distribution upon REEP co-expression (Right). Representative of three separate transfections. Scale bars: 25 µm.