(A) Effect of Sec16A downregulation on RNF183 subcellular localization. HeLa cells stably expressing RNF183-V5 were transfected with NC (1st, 3rd, 5th panels) or Sec16A (2nd, 4th, 6th panels) siRNAs. At 48 h after transfection, cells were subjected to immunofluorescence staining with anti-V5 (green) and anti-calnexin, GM130, or LAMP1 (red) antibodies, and DAPI (blue). (B) Effect of proteasome inhibition on RNF183 subcellular localization. HeLa cells stably expressing RNF183-V5 were transfected with NC (top panels) or Sec16A (middle and bottom panels) siRNAs. At 36 h after transfection, cells were incubated with (bottom panels) or without (top and middle panels) 10 μM MG132 for 12 h.