GRK Inhibitor Combo Pack 2

Figure 1. Chemical Structure of GRK2/3 Inhibitor (Cmpd 8h) and GRK5/6 Inhibitor (Cmpd 19). 

Figure 2. Inhibition of GRK-mediated β2 adrenergic receptor (β2) phosphorylation by GRK2/3 Inhibitor (Cmpd 8h). HEK293 ΔGRK3/5/6 (GRK2) or ΔGRK2/5/6 (GRK3) or ΔGRK2/3/6 (GRK5) or ΔGRK2/3/5 (GRK6) stably expressing the β2 were preincubated with increasing concentrations of the  GRK2/3 Inhibitor (Cmpd 8h) (30 min, 37°C) prior to treatment with 10 µM isoproterenol (ISO) (30 min, 37°C). Receptor phosphorylation was assessed using the 7TM phosphorylation assay and data were normalized to 10 µM ISO without inhibitor.

Figure 3. Comparison of GRK2 inhibition of GRK-mediated β2 adrenergic receptor (β2) phosphorylation by GRK2/3 Inhibitor (Cmpd 8h) or Compound 101. HEK293 ΔGRK3/5/6 stably expressing the β2 were preincubated with increasing concentrations of the  GRK2/3 Inhibitor (Cmpd 8h) or Compund 101 (30 min, 37°C) prior to treatment with 10 µM isoproterenol (ISO) (30 min, 37°C). Receptor phosphorylation was assessed using the 7TM phosphorylation assay and data were normalized to 10 µM ISO without inhibitor.

Figure 4. Comparison of GRK5 inhibition of GRK-mediated β2 adrenergic receptor (β2) phosphorylation by GRK5/6 Inhibitor (Cmpd 18) or GRK5/6 Inhibitor 2 (Cmpd 19). HEK293 ΔGRK2/3/6 stably expressing the β2 were preincubated with increasing concentrations of the GRK5/6 Inhibitor (Cmpd 18) or GRK5/6 Inhibitor 2 (Cmpd 19) (30 min, 37°C) prior to treatment with 10 µM isoproterenol (ISO) (30 min, 37°C). Receptor phosphorylation was assessed using the 7TM phosphorylation assay and data were normalized to 10 µM ISO without inhibitor.

Figure 5. Comparison of GRK6 inhibition of GRK-mediated β2 adrenergic receptor (β2) phosphorylation by GRK2/3 Inhibitor (Cmpd 8h) or GRK5/6 Inhibitor 2 (Cmpd 19). HEK293 ΔGRK2/3/5 stably expressing the β2 were preincubated with increasing concentrations of the GRK5/6 Inhibitor (Cmpd 18) or GRK5/6 Inhibitor 2 (Cmpd 19) (30 min, 37°C) prior to treatment with 10 µM isoproterenol (ISO) (30 min, 37°C). Receptor phosphorylation was assessed using the 7TM phosphorylation assay and data were normalized to 10 µM ISO without inhibitor.

Nina K Blum, Manuela C Kiefer, Angelika Decker, Laura Klement, Edda S F Matthees, Verena Weitzel, Falko Nagel, Babu Joseph, Julia Drube, David Uehling, Carsten Hoffmann, Stefan Schulz. Cell-based and isoform-selective G protein-coupled receptor kinase assays for comprehensive inhibitor evaluation Commun Biol 2026 Jan 16. doi: 10.1038/s42003-026-09568-0. PMID: 41545717