Figure 4.

Rli1 is a shuttling protein involved in ribosomal export. (A) A yeast strain, in which the endogenous RLI1 promoter was replaced by the Tet^OFF promoter, was transformed with Rpl25-GFP and Rps2-GFP plasmids. The cells were grown in liquid SDC-leu medium at 30°C. At early exponential growth (OD 0.2), doxycycline was added to a final concentration of 5 μg/ml. Cells were examined after 12 h of incubation. (B) The RLI1-GFP/xpo1-1 cells were grown in YPD at 30°C to OD₆₀₀ 0.2 before shift to 37°C. After 1.5 and 4 h of incubation at 37°C, cells were examined in the fluorescence microscope. (C) Rli1 mainly cosediments with 40S subunits and 80S ribosomes. Rli1-TAP was visualized in the fractions derived from the sucrose gradient by Western using anti-protein A antibodies.