Figure 2

GFP-Nup localization in npa mutants. Isolated assembly mutant strains along with the parental strain were grown to early log phase at 23° then shifted to the non-permissive temperature of 34° for 4 hours. Localization of GFP-Nic96p and Nup170p-GFP was visualized by direct fluorescence microscopy, and all GFP images were collected for the same exposure time. WT cells (SWY2089) maintain a characteristic punctate nuclear rim staining, indicative of NPC localization, throughout the temperature shift. In contrast, the mutants display various localization phenotypes including NPC clusters (npa43, G), cytoplasmic and nuclear foci (npa12, K), and a diminished GFP-Nup signal (npa67, O). Note that while Nup-GFP localization is already affected at 23° in npa43 (E) and npa67 (M), the phenotype is exacerbated at 34° (G and O).