Fig. 6. Syntaxin 8 must be anchored in the membrane to inhibit GFP-CFTR plasma membrane localization. We compared the intracellular localization of both proteins in COS-7 cells cotransfected with GFP-CFTR and Syn8 (A) or by GFP-CFTR and Syn8TM (B). Overexpressed (Aa) syntaxin 8 shows a predominantly perinuclear staining and also appears in a cytoplasm punctuated pattern. GFP-CFTR presents no plasma membrane localization (Ab), but is accumulated and colocalizes with syntaxin 8 only in the perinuclear region (arrows). (B) Soluble syntaxin 8 (Syn8TM) displays a continuous staining within the cell, but is predominantly accumulated in compartments where GFP-CFTR is present, notably at the plasma membrane. Bars, 10 µm.