Figure 1.

Localization of active Ras in the W303-1A wild-type strain after addition of 40 mM acetic acid. Cells transformed with YEpeGFP-RBD3 were grown in 2% glucose medium at 30°C until exponential phase, collected by centrifugation, and resuspended in medium adjusted to pH 3.0. Cells were then photographed with a Nikon fluorescence microscope, before and after addition of 40 Mm acetic acid. Colocalization of eGFP fluorescence and the red-fluorescent Rhodamine B hexyl ester is clearly visible five minutes after addition of the apoptotic stimulus.