Figure 4.

Effect of Hsp90 inhibitors on the kinetics and morphology of VSV-G^ts transport to the Golgi. (A) Time course of VSV-G^ts transport in the presence of 0.1% DMSO (control), 20 μM GA, or 50 μM radicicol. VSV^ts-infected cells were pretreated with drug for 60 min before transfer to the permissive temperature (32°C) to initiate ER export. (B) Morphological analysis of the effect of Hsp90 inhibitors on VSV-G^ts transport. Cells were pretreated with radicicol (50 μM) for 30 min at the restrictive temperature (40°C) before temperature shift to initiate ER export for 10 min at 32°C. Marker antibodies: ER, calnexin; cis/medial-Golgi, Man II or GM130. Bar, 10 μm. (C) Quantitation of overlap between VSV-G^ts and GM130 in Golgi stacks from at least 10 cells at the 0- and 10-min time point in the presence or absence radicicol (see Materials and Methods).