Cysteine 2.59(89) in the Second Transmembrane Domain of Human CB2 Receptor Is Accessible within the Ligand Binding Crevice: Evidence for Possible CB2 Deviation from a Rhodopsin Template

  title={Cysteine 2.59(89) in the Second Transmembrane Domain of Human CB2 Receptor Is Accessible within the Ligand Binding Crevice: Evidence for Possible CB2 Deviation from a Rhodopsin Template},
  author={Rundong Zhang and Dow P. Hurst and Judy Barnett-Norris and Patricia H. Reggio and Zhao-hui Song},
  journal={Molecular Pharmacology},
  pages={69 - 83}
In this study, the sensitivity of the CB2 receptor to methanethiosulfonate (MTS) derivatives was tested, and a native cysteine residue conferring the sensitivity was identified. By incubating human embryonic kidney 293 cells stably transfected with CB2 receptors and MTS derivatives such as MTS ethylammonium (MTSEA), [3H]HU-243 binding was inhibited. Pretreatment of the CB2 receptor with cannabinoid ligands prevented this inhibition, suggesting that MTSEA modification occurred within the binding… 
Mutation Studies of Ser7.39 and Ser2.60 in the Human CB1 Cannabinoid Receptor: Evidence for a Serine-Induced Bend in CB1 Transmembrane Helix 7
Results clearly suggest that Ser7.39, but not Ser2.60, plays a crucial role in mediating ligand specific interactions for CP55,940, HU210, and AM4056 at the human CB1 receptor.
Comparison of three GPCR structural templates for modeling of the P2Y12 nucleotide receptor
Ligand docking to the CXCR4-based model of the P2Y12R predicted poses of both reversibly and irreversibly-binding small molecules, consistent with observed pharmacology and mutagenesis studies.
CB2-Selective Cannabinoid Receptor Ligands: Synthesis, Pharmacological Evaluation, and Molecular Modeling Investigation of 1,8-Naphthyridin-2(1H)-one-3-carboxamides
A number of additional derivatives in which the same central scaffold has been variously functionalized in position 1 or 6 of the naphthyridine scaffold, showing high selectivity and affinity in the nanomolar range for the CB2 receptor.
Methods for the Development of In Silico GPCR Models.
6-Methoxy-N-alkyl isatin acylhydrazone derivatives as a novel series of potent selective cannabinoid receptor 2 inverse agonists: design, synthesis, and binding mode prediction.
A ligand-based homology model of the CB2 binding site was developed, and on the basis of the results, a general binding mode for this class of inverse agonists with CB2 is proposed.
Global fold of human cannabinoid type 2 receptor probed by solid‐state 13C‐, 15N‐MAS NMR and molecular dynamics simulations
The experimental NMR spectra matched the calculated spectra reasonably well indicating agreement of the global fold of the protein between experiment and simulations, and the 13C chemical shift distribution of Cα resonances was shown to be very sensitive to both the primary amino acid sequence and the secondary structure of CB2.
A Lipid Pathway for Ligand Binding Is Necessary for a Cannabinoid G Protein-coupled Receptor*
To the authors' knowledge, this is the first demonstration via unbiased molecular dynamics that a ligand can access the binding pocket of a class A G protein-coupled receptor via the lipid bilayer and the first demonstrated via molecular dynamics of Gprotein-cOUpled receptor activation triggered by aligand binding event.


A cysteine residue in the third membrane-spanning segment of the human D2 dopamine receptor is exposed in the binding-site crevice.
Positively charged M TS reagents irreversibly inhibited binding several hundredfold faster than a negatively charged MTS reagent, consistent with the affinity of the binding site for positively charged dopamine agonists and antagonists.
A lysine residue of the cannabinoid receptor is critical for receptor recognition by several agonists but not WIN55212-2.
Results demonstrate that Lys192 is critical for receptor binding by HU-210, CP-55940, and anandamide, and that WIN55212-2 must interact with the cannabinoid receptor through at least one point of interaction that is distinct from those of the three other agonists.
Role of a conserved lysine residue in the peripheral cannabinoid receptor (CB2): evidence for subtype specificity.
It is found that a high-affinity site for (-)-3-[2-hydroxyl-4-(1, 1-dimethylheptyl)phenyl]-4-[3-Hydroxyl propyl] cyclohexan-1-ol (CP-55,940) in the region of helices 3, 6, and 7 is identified, which could lead to subtype specificity.
Agonist-induced Conformational Changes at the Cytoplasmic Side of Transmembrane Segment 6 in the β2 Adrenergic Receptor Mapped by Site-selective Fluorescent Labeling*
The data suggest that activation of G protein-coupled receptors, which are activated by “diffusible” ligands, involves a structural rearrangement corresponding to the cytoplasmic part of transmembrane segment (TM) 6.
Electrostatic and aromatic microdomains within the binding-site crevice of the D2 receptor: contributions of the second membrane-spanning segment.
It is inferred that the side chains of the residues at the 11 reactive loci are on the water-accessible surface of the binding-site crevice and that 9 of these are occluded by bound antagonist, which suggests an alpha-helical conformation.
Constitutive Activation of the β2 Adrenergic Receptor Alters the Orientation of Its Sixth Membrane-spanning Segment*
The binding site of the β2adrenergic receptor, like that of other homologous G-protein-coupled receptors, is contained within a water-accessible crevice formed among its seven membrane-spanning
Agonist alkyl tail interaction with cannabinoid CB1 receptor V6.43/I6.46 groove induces a helix 6 active conformation
It is hypothesized that the profound flexibility differences between wild-type (WT) CB1 vs. WT CB2 TMH 6 revealed by CM calculations may be due to the size of residue 6.49 which immediately precedes P6.50 of the CWXP motif, and that interaction with this motif may trigger receptor activation.
Agonist-induced conformational changes in the G-protein-coupling domain of the β2 adrenergic receptor
The authors' studies, when compared with studies of activation in rhodopsin, indicate a general mechanism for GPCR activation; however, a notable difference is the relatively slow kinetics of the conformational changes in the β2AR, which may reflect the different energetics of activation by diffusible ligands.