Discovery of novel chemotypes to a G-protein-coupled receptor through ligand-steered homology modeling and structure-based virtual screening

J Med Chem. 2008 Feb 14;51(3):581-8. doi: 10.1021/jm070759m. Epub 2008 Jan 17.

Abstract

Melanin-concentrating hormone receptor 1 (MCH-R1) is a G-protein-coupled receptor (GPCR) and a target for the development of therapeutics for obesity. The structure-based development of MCH-R1 and other GPCR antagonists is hampered by the lack of an available experimentally determined atomic structure. A ligand-steered homology modeling approach has been developed (where information about existing ligands is used explicitly to shape and optimize the binding site) followed by docking-based virtual screening. Top scoring compounds identified virtually were tested experimentally in an MCH-R1 competitive binding assay, and six novel chemotypes as low micromolar affinity antagonist "hits" were identified. This success rate is more than a 10-fold improvement over random high-throughput screening, which supports our ligand-steered method. Clearly, the ligand-steered homology modeling method reduces the uncertainty of structure modeling for difficult targets like GPCRs.

MeSH terms

  • Animals
  • Binding Sites
  • Binding, Competitive
  • CHO Cells
  • Cattle
  • Cricetinae
  • Cricetulus
  • Databases, Factual
  • Humans
  • Ligands*
  • Models, Molecular*
  • Receptors, Pituitary Hormone / antagonists & inhibitors*
  • Receptors, Pituitary Hormone / chemistry*
  • Receptors, Pituitary Hormone / metabolism
  • Receptors, Somatostatin / antagonists & inhibitors*
  • Receptors, Somatostatin / chemistry*
  • Receptors, Somatostatin / metabolism
  • Rhodopsin / chemistry
  • Sequence Homology, Amino Acid
  • Stochastic Processes
  • Structure-Activity Relationship
  • Thermodynamics

Substances

  • Ligands
  • MCHR1 protein, human
  • Receptors, Pituitary Hormone
  • Receptors, Somatostatin
  • melanin-concentrating hormone receptor
  • Rhodopsin