1. Human Cannabinoid Receptor 2 Ligand-Interaction Motif: Transmembrane Helix 2 Cysteine, C2.59(89), as Determinant of Classical Cannabinoid Agonist Activity and Binding Pose
- Author
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Han Zhou, Xiaoyu Ma, David R. Janero, Xin Sun, Aneetha Halikhedkar, Yan Peng, Pusheng Fan, Richard W. Mercier, Ganesh A. Thakur, and Alexandros Makriyannis
- Subjects
0301 basic medicine ,Agonist ,Protein Conformation, alpha-Helical ,Physiology ,medicine.drug_class ,Cognitive Neuroscience ,medicine.medical_treatment ,Ligands ,Biochemistry ,Receptor, Cannabinoid, CB2 ,03 medical and health sciences ,0302 clinical medicine ,Cannabinoid receptor type 2 ,medicine ,Humans ,Protein Interaction Domains and Motifs ,Cysteine ,G protein-coupled receptor ,Cannabinoid Receptor Agonists ,Binding Sites ,Chemistry ,Rational design ,Cell Biology ,General Medicine ,Transmembrane domain ,030104 developmental biology ,HEK293 Cells ,Cannabinoid ,Signal transduction ,030217 neurology & neurosurgery - Abstract
Cannabinoid receptor 2 (CB2R)-dependent signaling is implicated in neuronal physiology and immune surveillance by brain microglia. Selective CB2R agonists hold therapeutic promise for inflammatory and other neurological disorders. Information on human CB2R (hCB2R) ligand-binding and functional domains is needed to inform the rational design and optimization of candidate druglike hCB2R agonists. Prior demonstration that hCB2R transmembrane helix 2 (TMH2) cysteine C2.59(89) reacts with small-molecule methanethiosulfonates showed that this cysteine residue is accessible to sulfhydryl derivatization reagents. We now report the design and application of two novel, pharmacologically active, high-affinity molecular probes, AM4073 and AM4099, as chemical reporters to interrogate directly the interaction of classical cannabinoid agonists with hCB2R cysteine residues. AM4073 has one electrophilic isothiocyanate (NCS) functionality at the C9 position of its cyclohexenyl C-ring, whereas AM4099 has NCS groups at that position and at the terminus of its aromatic A-ring C3 side chain. Pretreatment of wild-type hCB2R with either probe reduced subsequent [
- Published
- 2017