Figure 7.

ARF6 colocalize with HRP only on prolonged exposure to the tracer. Cells expressing wild-type ARF6 were incubated for 60 min with HRP, fixed, and then processed for cryoimmunogold labeling. Samples were labeled with an anti-ARF6 polyclonal antibody followed by protein A–gold particles (10 nm) and then with an anti-HRP antibody followed by protein A–gold particles (5 nm). With prolonged exposure to HRP some colocalization (⩽10%) with ARF6-positive vesicles was observed (arrow, inset at higher magnification). e, endosomes; m, mitochondria; n, nucleus; ne, nuclear envelope; p, plasma membrane. Bar, 200 nm.