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

@article{Zhang2005Cysteine2I,
  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},
  year={2005},
  volume={68},
  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… 
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