Figure 4. Phosphorylation of GPCR and Non-receptor Substrates by GRK2 Kinase-Domain Mutants.
Four mutants (Y281A, P473E, V477D, and I485A) were over-expressed in COS-1 or Sf9 insect cells and purified. Kinase assays were carried out with rhodopsin (A), β2AR in phosphatidylcholine vesicles (B), tubulin (C), α-synuclein (D), RESA peptide (E), and RASASA peptide (F) as described in Experimental Procedures. Error bars indicate SEM. One-way ANOVA was used to compare statistical significance of differences relative to WT. *, p<0.05; **, p<0.01.