Figure 8.

An early endocytic intermediate is accumulated in vps8 but not vps1 cells. (A) Time course of FM 4-64 endocytosis. Exponentially growing cells were incubated on ice for 30 min with 40 μM FM 4-64. Cells were then washed and incubated for an additional 20 or 60 min at 30°C. At 60 min in vps8 (WLX16-1A) and ypt51 (WLY65) cells, FM 4-64 is accumulated in an endocytic intermediate similar to that seen at 20 min in wild-type cells (L3852). (B) FM 4-64 endocytosis is delayed in vps8 at a step before the prevacuolar compartment. After labeling for 15 min with FM 4-64, cells were washed, resuspended, and incubated for 1 h at 30°C before visualization and photography. vps8 (ACY76), vps27 (ACY33), vps8 vps27 (WLX20-5D), and vps1 (ACX58-3C) cells are shown. The pattern of FM 4-64 accumulation in vps8 vps27 double mutants resembles that seen in vps8 cells.