Figure 5.
Localization of GGA1 at the electron microscope level. NRK cells were permeabilized by freezing and thawing, then allowed to recruit proteins from pig brain cytosol in the presence of ATP, an ATP-regenerating system, and GTPγS. Frozen thin sections were labeled with an antibody against GGA1, followed by protein A coupled to 15-nm colloidal gold. Labeling can be seen to be associated with the Golgi stack and with tubulovesicular membranes in the Golgi region. Clathrin-coated budding profiles can be seen in the same vicinity (arrowheads), indicating that these membranes correspond to trans-Golgi cisternae and the TGN. Bar, 200 nm.