Structures of the human cholecystokinin receptors bound to agonists and antagonists

Nat Chem Biol. 2021 Dec;17(12):1230-1237. doi: 10.1038/s41589-021-00866-8. Epub 2021 Sep 23.


Cholecystokinin receptors, CCKAR and CCKBR, are important neurointestinal peptide hormone receptors and play a vital role in food intake and appetite regulation. Here, we report three crystal structures of the human CCKAR in complex with different ligands, including one peptide agonist and two small-molecule antagonists, as well as two cryo-electron microscopy structures of CCKBR-gastrin in complex with Gi2 and Gq, respectively. These structures reveal the recognition pattern of different ligand types and the molecular basis of peptide selectivity in the cholecystokinin receptor family. By comparing receptor structures in different conformational states, a stepwise activation process of cholecystokinin receptors is proposed. Combined with pharmacological data, our results provide atomic details for differential ligand recognition and receptor activation mechanisms. These insights will facilitate the discovery of potential therapeutics targeting cholecystokinin receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Cryoelectron Microscopy
  • Crystallization
  • Devazepide / chemistry*
  • Humans
  • Indoleacetic Acids / chemistry
  • Ligands
  • Models, Molecular
  • Protein Binding
  • Protein Conformation
  • Receptors, Cholecystokinin / chemistry*
  • Receptors, Cholecystokinin / genetics
  • Structure-Activity Relationship
  • Thiazoles / chemistry


  • Indoleacetic Acids
  • Ligands
  • Receptors, Cholecystokinin
  • Thiazoles
  • SR 27897
  • Devazepide