FIG. 5.
TAP derivatives having a single nucleoporin-binding domain translocate specific CTE RNA cargoes across the NPC. (A and B) Xenopus oocyte nuclei were injected with mixtures of 32P-labeled RNAs and purified recombinant proteins as indicated. RNA samples from total oocytes (T) and nuclear (N) and cytoplasmic (C) fractions were collected immediately after injection (t0; lanes 1 to 3) or 90 min after injection in panel A and analyzed as described in the legend to Fig. 4. In panel B, samples were collected 120 min after injection and analyzed in 10% acrylamide-7 M urea denaturing gels. The concentration of recombinant proteins in the injected samples was 3 μM. The numbers below the panels represent the percentage of a given RNA in the cytoplasm in the presence of the proteins indicated above the lanes. The nuclear localization of U6Δss RNA and the export of tRNA (>94%) were not affected by any of the injected proteins, and these values are not included. The mature products and intermediates of the splicing reaction are indicated diagrammatically on the left of panel B. The solid triangle represents the M38 CTE. wt, wild type.