FIGURE 1.

Binding of impβ to GDP- and GppNHp-loaded Ran in the presence and absence of RanBP1. Proteins were incubated for 30 min at room temperature in a reaction buffer containing 50 mM Tris (pH 7.5), 200 mM NaCl, and 1 mM DTT. After incubation, the mixtures were loaded onto a 10% native polyacrylamide gel. Proteins were present in equimolar amounts, except RanBP1, which was added in excess.