Figure 2.

β-arr1 spin-labeled cysteine mutants maintained their ability to bind to STAM1, as assessed by pulldown experiments. Equimolar amounts of purified β-arr1-WT or indicated β-arr1 cysteine mutants (0.4 μm) were incubated with or without purified STAM1– (3 μm) for 20 min at 37˚C. Complexes were immobilized by incubation with Talon cobalt resin, and after washing, proteins were eluted in buffer with 200 mM imidazole and analyzed by immunoblotting. Representative blots are shown for β-arr1 double cysteine mutants (a) and single cysteine mutants (b and c).