Figure 5.

SacIp phosphatase activity is required for normal vacuole morphology. sac1^ts cells were grown to early log phase at 26°C, and vacuoles were labeled with the vital dye FM4-64 for 15 min (see MATERIALS AND METHODS). After labeling, cells were chased for 45 min and shifted to the indicated temperature for 2 h. On the right, cells were observed by Nomarski optics. On the left, identical fields are shown under fluorescent illumination (rhodamine channel). sac1^ts cells at 26°C are shown on top, and sac1^ts cells after a 2-h shift to 38°C are shown below. These cells are representative of >90% of cells observed.