Figure 5.

Gβγ binding specificity of GRK2 and GRK3 carboxyl termini. (A) Recombinant Gβ₁, Gβ₂, or Gβ₃ subunits from Sf9 cells were subjected to Western blot analysis using Gβ-specific antibodies. (B) Purified GST, GST-GRK2ct, or GST-GRK3ct proteins were incubated with purified bovine brain Gβγ in the presence of glutathione-Sepharose beads. Protein–bead complexes were washed and analyzed for Gβ isoforms by Western blotting using the specific Gβ₁, Gβ₂, or Gβ₃ antibodies. (C) GST-GRK2ct or GST-GRK3ct proteins were incubated with purified recombinant Gβ₁γ₅ or Gβ₃γ₅ and analyzed for complex formation as previously described. Blots were developed using Gβ_common antibodies. A Western blot representative of at least three independent experiments is shown.