Fig. 4.

Effect of three Imp-α mutations on nuclear import. The three single-site Imp-α mutations D192K (green), E396R (light blue), and R39D (orange) all reduced the interaction of Imp-α with CAS. Quantified in the bar graphs are the frequency (as percentage of the total) that each of the six outcomes depicted in Fig. 3A was observed for the three mutants and wild-type (WT) Imp-α . Only the CAS-free form of Imp-α was observed to interact with NPCs from the cytoplasmic side (path 1). For wild-type Imp-α, the presence or absence of a cargo molecule was assumed on the basis of the model in Fig. 3F. The cargo is not expected to be present in any of the species depicted for the R39D and D192K mutants (Fig. S2A). Imp-α/CAS complex formation efficiencies (path 3) are indicated as percentages, color coded to the various mutants (n = 207–287; Table S1). Conditions are the same as in Fig. 1A.