Fig. 5. Imp13 mediates nuclear export of eIF1A. (A) Fluorescent GST–eIF1A (1 µM) was allowed to diffuse for 6 min into nuclei. One sample was fixed immediately. The others were incubated with the indicated additions for a further 5 min before they were also fixed. The presence of Imp13 (2 µM), Ran and energy resulted in efficient eIF1A export and complete loss of the nucleolar signal. (B) A comparison of the indicated combinations of nuclear transport receptors (2 µM) in their export activity towards eIF1A. Export was performed as in (A).