Figure 2.

Golgin-84 is localized to the cis-Golgi network. (a–e) A431 cells were processed for cryoelectron microscopy and labeled with polyclonal antibodies to golgin-84 (a–d) or GM130 (e) followed by secondary antibodies coupled to 10-nm gold. Arrows indicate ER budding profiles, and arrowheads indicate golgin-84 (a–d) or GM130 (e) labeling. (f–g) Quantitation of golgin-84 and GM130 labeling of cryosections. The relative number of gold particles over Golgi cisternae, tubulo-vesicular profiles lateral to the Golgi stack, tubulo-vesicular profiles adjacent to the cis face of the stack (central), or over other structures was quantitated in gluteraldehyde-fixed A431 cells (f) and paraformaldehyde-fixed HeLa cells (g) as described in the Materials and methods section. Note that golgin-84 labeling is present on the cis-most cisternae and more predominantly on tubulo-vesicular profiles lateral to the stack, whereas GM130 labeling is mainly on the cis-most cisternae of the stack (a–c). Bars, 200 nm.