Molecular basis for small molecule inhibition of G protein-coupled receptor kinases

ACS Chem Biol. 2015 Jan 16;10(1):246-56. doi: 10.1021/cb5003976. Epub 2014 Jul 14.


Small molecules that inhibit the protein kinase A, G, and C (AGC) family of serine/threonine kinases can exert profound effects on cell homeostasis and thereby regulate fundamental processes such as heart rate, blood pressure, and metabolism, but there is not yet a clinically approved drug in the United States selective for a member of this family. One subfamily of AGC kinases, the G protein-coupled receptor (GPCR) kinases (GRKs), initiates the desensitization of active GPCRs. Of these, GRK2 has been directly implicated in the progression of heart failure. Thus, there is great interest in the identification of GRK2-specific chemical probes that can be further developed into therapeutics. Herein, we compare crystal structures of small molecule inhibitors in complex with GRK2 to those of highly selective compounds in complex with Rho-associated coiled-coil containing kinase 1 (ROCK1), a closely related AGC kinase. This analysis suggests that reduced hydrogen-bond formation with the hinge of the kinase domain, occupation of the hydrophobic subsite, and, consequently, higher buried surface area are key drivers of potency and selectivity among GRK inhibitors.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • Drug Discovery
  • G-Protein-Coupled Receptor Kinase 2 / antagonists & inhibitors
  • G-Protein-Coupled Receptor Kinase 2 / genetics
  • G-Protein-Coupled Receptor Kinases / antagonists & inhibitors*
  • G-Protein-Coupled Receptor Kinases / genetics
  • Humans
  • Hydrogen Bonding
  • Models, Molecular
  • Protein Kinase Inhibitors / chemistry
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Structure, Tertiary
  • Small Molecule Libraries / chemistry
  • Small Molecule Libraries / pharmacology*
  • rho-Associated Kinases / antagonists & inhibitors
  • rho-Associated Kinases / genetics


  • Protein Kinase Inhibitors
  • Small Molecule Libraries
  • rho-Associated Kinases
  • G-Protein-Coupled Receptor Kinase 2
  • G-Protein-Coupled Receptor Kinases