Figure 3.

(A) At 42°C, Npl3-27p, but not mRNA exits the nucleus. Both strains, npl3-27 (left) and xpo1-1 npl3-27 (right), were grown to log phase, then shifted to 42°C for 15 min, before they were prepared for IF with α-Npl3p (top), oligo[d(T₅₀)] probe (middle), and a SSA4 probe (bottom). (B) Yeast lysates of the same strains were prepared after they were grown to log phase and either incubated at 37°C for 3 hr (lanes 1,2) or to 42°C for 15 min (lanes 3,4) without [− (lanes 1,3)] or with cycloheximide addition [ + (lanes 2,4)]. The lysates were separated on a 12% SDS-polyacrylamide gel and analyzed on a Western blot with antibodies against Npl3p. (C) npl3-27 cells overexpressing MTR10 on a 2μ plasmid were grown to log phase and shifted to 42°C for 15 min. (D) Wild-type strains were grown to log phase before they were shifted to 42°C for different times. The localization of Npl3p was monitored by immunofluorescence.