Structural basis for μ-opioid receptor binding and activation.

Journal Article (Journal Article)

Opioids that stimulate the μ-opioid receptor (MOR1) are the most frequently prescribed and effective analgesics. Here we present a structural model of MOR1. Molecular dynamics simulations show a ligand-dependent increase in the conformational flexibility of the third intracellular loop that couples with the G protein complex. These simulations likewise identified residues that form frequent contacts with ligands. We validated the binding residues using site-directed mutagenesis coupled with radioligand binding and functional assays. The model was used to blindly screen a library of ∼1.2 million compounds. From the 34 compounds predicted to be strong binders, the top three candidates were examined using biochemical assays. One compound showed high efficacy and potency. Post hoc testing revealed this compound to be nalmefene, a potent clinically used antagonist, thus further validating the model. In summary, the MOR1 model provides a tool for elucidating the structural mechanism of ligand-initiated cell signaling and for screening novel analgesics.

Full Text

Duke Authors

Cited Authors

  • Serohijos, AWR; Yin, S; Ding, F; Gauthier, J; Gibson, DG; Maixner, W; Dokholyan, NV; Diatchenko, L

Published Date

  • November 9, 2011

Published In

Volume / Issue

  • 19 / 11

Start / End Page

  • 1683 - 1690

PubMed ID

  • 22078567

Pubmed Central ID

  • PMC3217204

Electronic International Standard Serial Number (EISSN)

  • 1878-4186

Digital Object Identifier (DOI)

  • 10.1016/j.str.2011.08.003

Language

  • eng

Conference Location

  • United States