Figure 2.

Time course of H89 inhibition of transport of VSV-G from the TGN to the cell surface. Infected, radiolabeled cells were incubated at 20°C for 2 h. They were then transferred to 37°C to allow radiolabeled VSV-G retained in the TGN to be transported to the cell surface. Transport was arrested at the indicated time points; cells were transferred on ice and incubated or not (control) with 50 μM of H89 for 30 min. In the case of H89-treated cells, transport was reestablished by returning the cells to 37°C to complete a 40 min transport period in the continuous presence of this agent. VSV-G was immunoprecipitated from the cell surface and subjected to SDS/PAGE analysis. (A) Access to the cell surface of VSV-G is compared in untreated, control cells and cells incubated with H89. (B) The amount of VSV-G reaching the cell surface is expressed as percentage of that in control cells. Values were normalized for the total amount of VSV-G within the cells. They are representative of three independent experiments.