FIG. 3.

Export of GFP-Rpb4p and Rpb7p-RFP during severe stresses is independent of transcription. (A) Images of nup49-313(ts) rpb1-1(ts) cells expressing both GFP-Rpb4p and Rpb7p-RFP (yMS4) in the mid-logarithmic phase at 24°C (left panels) or after 2 h under the indicated stress conditions in the presence of 50 μg/ml cycloheximide. The nonstressed sample was equally treated with cycloheximide and further incubated in parallel with the stress-treated cultures. The starved and EtOH-treated cultures were incubated at 37°C to inactivate transcription. The bars represent 5μ. (B) Export kinetics, determined as described for Fig. 2D, of Rpb7p-RFP after a shift from 24°C to 42°C in the absence (Cont.) or presence (Φ) of the transcription inhibitor 1,10-phenanthroline (100 μg/ml).