Fig. 2. Orientation of GFP on the C-terminus of VatM. Cells expressing VatM-GFP were fed TRITC-dextran, and endosomes were isolated on a Percoll gradient. Endosomes, identified by TRITC-dextran fluorescence (A), were rimmed with green fluorescence (B) from VatM-GFP in the endosomal membranes; C shows the two images overlaid. Following brief treatment with Proteinase K, TRITC-dextran was still present in the endosomes (D), although the green fluorescence (E) had disappeared from endosomal membranes; F shows the two images overlaid.