Figure 3.

Dispersal of GFP-Sft2p in a sec18 mutant. The upper panels show a control with SEC⁺ cells, the same group of cells being imaged at 20°C, 10 min after initiation of warming to 37°C (i.e., after about 8 min at this temperature), and after re-equilibration to 20°C (20 min after heating stopped). The lower panels show the equivalent experiment with sec18 cells. In the 37°C panel one cell (outlined in white) is printed with the brightness increased, to show more clearly the lack of punctate staining under these conditions. Images are projections of four optical sections. The graphs show smoothed profiles of the distribution of pixel brightness in groups of five to eight cells imaged successively at low and high temperature, obtained as described in MATERIALS AND METHODS. Note the loss of the brighter pixels at 37°C in the sec18 cells.