Table I.

GTP-γ-S, But Not IgGs Directed Against Erd2p, β-COP, or p23 Inhibit the Transport of CTX–K63 from the Plasma Membrane (PM) to the Golgi

		Localization of CTX-A–K63
		PM		Golgi
		% of counted microinjected cells
Controls		5		95
BSA		6		94
GTP-γ-S		73		27
Anti-Erd2p		10		90
Anti-β-COP		7		93
Anti-p23		12		88

The IgGs or GTP-γ-S were microinjected 10 min before initiating the uptake of CTX– K63 as in Fig. 2. The cells were fixed 40 min after start of CTX–K63 uptake and prepared for immunofluorescence using Cy3-labeled antibodies against CTX-A–K63. Cells microinjected with GTP-γ-S were identified by coinjection of dye-labeled BSA. Cells injected with the various antibodies were identified by coinjecting Cy2-labeled antibodies of the same kind that had been mixed with non-labeled antibodies at a 1:3 ratio. In each group 25–30 microinjected cells were analyzed.