FIG. 3.

Efficient localization of YopM to the yeast nucleus requires functional vesicular trafficking. (A) yEGFP-YopM was expressed in S. cerevisiae RCD224 (wild type) and a temperature-sensitive sec18-1 S. cerevisiae strain. The localization of green fluorescence is compared for the two strains at the permissive temperature of 26°C, where both strains showed nuclear localization of YopM, and at the nonpermissive temperature for the sec18-1 strain (37°C), where nuclear localization occurred only in the wild-type yeast. (B) sec18-1 S. cerevisiae expressing yEGFP-YopM for 2 h was shifted to the nonpermissive temperature of 37°C for 5 h and then kept at 37°C for a further 2 h (left panel) or shifted back to the permissive temperature for 2 h (right panel) to determine if the inhibition of nuclear localization was reversible.