Figure 6.

API traffic is defective in vti1-11 cells. Cells were grown and labeled 15 min at 24°C, or shifted to 36°C for 15 min, labeled for 10 min, and chased for the indicated length of time. API was immunoprecipitated and separated by SDS-PAGE. A phosphorimager was used for quantification. (A) In wild-type cells (WT) pro-API transport to the vacuole and processing to mAPI was completed after a 120-min chase at 36°C, whereas it was tightly blocked in vam3Δ cells. (B) API traffic in vti1-11 cells was only slightly slower than in wild-type cells at 24°C. Processing of API was severely inhibited in vti1-11 cells at the restrictive temperature.