Staufen1 depletion decreases plasma membrane-associated Gag and results in intracellular clustering of Gag-Gag BiFC signals. HeLa cells were co-transfected with pCMV-Rev, Gag-VN and Gag-VC plasmids with control non-silencing siRNA (siNS), Staufen1 siRNA (siStaufen1) or Staufen1-HA. At 24 hr post-transfection cells were harvested for western blotting for Staufen1, Gag, Caveolin-1 and TSC2 (as loading controls) (A) or stained for lipid rafts in live cells. BiFC signals and lipid raft (CT-B) staining were captured by laser scanning confocal microscopy in cells transfected with siNS (B), siStaufen1 (C) or Staufen1-HA (D). Black and white images of lipid rafts (CT-B) and Gag-Gag BiFC signals and merged colour representations are shown. The insets are magnifications of boxed areas. The size bars are equal to 10 μm.