Ric-8A dissociates the LGN/Gαi-1/NuMA complex, activating myristoylated Gαi-1 and liberating NuMA. LGN/Gαi-1/NuMA complex (10 μM, ≈40 μM Gαi-1) was incubated for 10 (red) or 30 (blue) min at 30°C with 100 μM GDP (A), 100 μM GTP[γS] (B), 100 μM GDP and 1 μM Ric-8A (C), or 100 μM GTP[γS] and 1 μM Ric-8A (D). The reaction mixtures were loaded onto tandem Superdex 75/200 columns and resolved. Fractions from each experiment were analyzed by SDS/PAGE. Each silver-stained gel is shown below the UV absorbance of the gel filtration eluate. The positions of gel filtration mass standards and the fractions where NuMA dimer appeared are noted.