Skip to main content
. Author manuscript; available in PMC: 2016 Feb 20.
Published in final edited form as: Nature. 2015 Aug 5;524(7565):315–321. doi: 10.1038/nature14886

Figure 5. Rearrangement of a conserved polar network.

Figure 5

a, b Comparison of the water-mediated polar network in the active μOR and high-resolution inactive δOR (PDB ID: 4N6H). To simplify comparisons between different receptors, only Ballesteros-Weinstein numbers are used to label amino acid side chains. The network extends from the orthosteric ligand-binding site to the G protein-coupling domain of the receptor. c, The active structure of μOR reveals the basis for sodium ion allosteric regulation of GPCR function. Rearrangement of S3.39 and N3.35 eliminates the sodium ion coordination site in the active state. d, Conserved hydrogen bonding network in the NPxxY region between active μOR and rhodopsin.