(E) GST-fusion constructs of the Xenopus Nup53 RRM domain (aa 162-267, control) full-length Xenopus Nup50 and the two mouse Nup50 orthologues were incubated with Xenopus egg extracts. Starting material as well as bound proteins were analyzed by Western blotting with indicated antibodies The right panel shows the average MEL28/ELYS, Nup153, importin β and ran bead bound signal from two independent experiments normalized to their respective Xenopus signal. Data points from individual experiments are indicated. 