Identification of Various Allosteric Interaction Sites on M1 Muscarinic Receptor Using 125I-Met35-Oxidized Muscarinic Toxin 7

@article{FruchartGaillard2006IdentificationOV,
  title={Identification of Various Allosteric Interaction Sites on M1 Muscarinic Receptor Using 125I-Met35-Oxidized Muscarinic Toxin 7},
  author={Carole Fruchart-Gaillard and Gilles Mourier and Catherine Marquer and André Ménez and Denis Servent},
  journal={Molecular Pharmacology},
  year={2006},
  volume={69},
  pages={1641 - 1651}
}
Monoiodinated, Met35-oxidized muscarinic toxin 7 (MT7ox) was synthesized, and its affinity constants for free or N-methyl scopolamine (NMS)-occupied hM1 receptor were measured directly by equilibrium and kinetic binding experiments. Identical values were obtained with the two types of assay methods, 14 pM and 0.9 nM in free or NMS-liganded receptor states, respectively, highlighting a strong negative cooperativity between this allosteric toxin and NMS. Identical results were obtained with… 
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