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Desformylflustrabromine (dFBr) and [3H]dFBr-Labeled Binding Sites in a Nicotinic Acetylcholine Receptor.
Hamouda AK
,
Wang ZJ
,
Stewart DS
,
Jain AD
,
Glennon RA
,
Cohen JB
.
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Desformylflustrabromine (dFBr) is a positive allosteric modulator (PAM) of α4β2 and α2β2 nAChRs that, at concentrations >1 µM, also inhibits these receptors and α7 nAChRs. However, its interactions with muscle-type nAChRs have not been characterized, and the locations of its binding site(s) in any nAChR are not known. We report here that dFBr inhibits human muscle (αβεδ) and Torpedo (αβγδ) nAChR expressed in Xenopus oocytes with IC50 values of ∼ 1 μM. dFBr also inhibited the equilibrium binding of ion channel blockers to Torpedo nAChRs with higher affinity in the nAChR desensitized state ([(3)H]phencyclidine; IC50 = 4 μM) than in the resting state ([(3)H]tetracaine; IC50 = 60 μM), whereas it bound with only very low affinity to the ACh binding sites ([(3)H]ACh, IC50 = 1 mM). Upon irradiation at 312 nm, [(3)H]dFBr photoincorporated into amino acids within the Torpedo nAChR ion channel with the efficiency of photoincorporation enhanced in the presence of agonist and the agonist-enhanced photolabeling inhibitable by phencyclidine. In the presence of agonist, [(3)H]dFBr also photolabeled amino acids in the nAChR extracellular domain within binding pockets identified previously for the nonselective nAChR PAMs galantamine and physostigmine at the canonical α-γ interface containing the transmitter binding sites and at the noncanonical δ-β subunit interface. These results establish that dFBr inhibits muscle-type nAChR by binding in the ion channel and that [(3)H]dFBr is a photoaffinity probe with broad amino acid side chain reactivity.
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Correction to "Desformylflustrabromine (dFBr) and [3H]dFBr-Labeled Binding Sites in a Nicotinic Acetylcholine Receptor".
2015, Pubmed
,
Correction to "Desformylflustrabromine (dFBr) and [3H]dFBr-Labeled Binding Sites in a Nicotinic Acetylcholine Receptor".
2015,
Pubmed
Arevalo,
Gating-enhanced accessibility of hydrophobic sites within the transmembrane region of the nicotinic acetylcholine receptor's {delta}-subunit. A time-resolved photolabeling study.
2005,
Pubmed
Arias,
Positive and negative modulation of nicotinic receptors.
2010,
Pubmed
Bertrand,
Positive allosteric modulation of the alpha7 nicotinic acetylcholine receptor: ligand interactions with distinct binding sites and evidence for a prominent role of the M2-M3 segment.
2008,
Pubmed
,
Xenbase
Bertrand,
Allosteric modulation of nicotinic acetylcholine receptors.
2007,
Pubmed
Blanton,
Identifying the lipid-protein interface of the Torpedo nicotinic acetylcholine receptor: secondary structure implications.
1994,
Pubmed
Celie,
Nicotine and carbamylcholine binding to nicotinic acetylcholine receptors as studied in AChBP crystal structures.
2004,
Pubmed
Changeux,
Nicotinic receptors, allosteric proteins and medicine.
2008,
Pubmed
Chiara,
Photoaffinity labeling the propofol binding site in GLIC.
2014,
Pubmed
,
Xenbase
Chiara,
Identification of nicotinic acetylcholine receptor amino acids photolabeled by the volatile anesthetic halothane.
2003,
Pubmed
Chiara,
Time-resolved photolabeling of the nicotinic acetylcholine receptor by [3H]azietomidate, an open-state inhibitor.
2009,
Pubmed
,
Xenbase
Chiara,
[(3)H]chlorpromazine photolabeling of the torpedo nicotinic acetylcholine receptor identifies two state-dependent binding sites in the ion channel.
2009,
Pubmed
Corringer,
Structure and pharmacology of pentameric receptor channels: from bacteria to brain.
2012,
Pubmed
daCosta,
Single-channel and structural foundations of neuronal α7 acetylcholine receptor potentiation.
2011,
Pubmed
Dani,
Nicotinic acetylcholine receptors and nicotinic cholinergic mechanisms of the central nervous system.
2007,
Pubmed
Faghih,
Allosteric modulators of the alpha7 nicotinic acetylcholine receptor.
2008,
Pubmed
Filatov,
The role of conserved leucines in the M2 domain of the acetylcholine receptor in channel gating.
1995,
Pubmed
,
Xenbase
Gallagher,
Identification of amino acids of the torpedo nicotinic acetylcholine receptor contributing to the binding site for the noncompetitive antagonist [(3)H]tetracaine.
1999,
Pubmed
Garcia,
[3H]Benzophenone photolabeling identifies state-dependent changes in nicotinic acetylcholine receptor structure.
2007,
Pubmed
,
Xenbase
German,
Deconstruction of the α4β2 nicotinic acetylcholine receptor positive allosteric modulator desformylflustrabromine.
2011,
Pubmed
,
Xenbase
Giraudat,
Structure of the high-affinity binding site for noncompetitive blockers of the acetylcholine receptor: serine-262 of the delta subunit is labeled by [3H]chlorpromazine.
1986,
Pubmed
Gotti,
Neuronal nicotinic receptors: from structure to pathology.
2004,
Pubmed
Gotti,
Structural and functional diversity of native brain neuronal nicotinic receptors.
2009,
Pubmed
Grishin,
Alpha-conotoxin AuIB isomers exhibit distinct inhibitory mechanisms and differential sensitivity to stoichiometry of alpha3beta4 nicotinic acetylcholine receptors.
2010,
Pubmed
,
Xenbase
Hamouda,
Multiple transmembrane binding sites for p-trifluoromethyldiazirinyl-etomidate, a photoreactive Torpedo nicotinic acetylcholine receptor allosteric inhibitor.
2011,
Pubmed
Hamouda,
Identifying barbiturate binding sites in a nicotinic acetylcholine receptor with [3H]allyl m-trifluoromethyldiazirine mephobarbital, a photoreactive barbiturate.
2014,
Pubmed
,
Xenbase
Hamouda,
Physostigmine and galanthamine bind in the presence of agonist at the canonical and noncanonical subunit interfaces of a nicotinic acetylcholine receptor.
2013,
Pubmed
Hassaine,
X-ray structure of the mouse serotonin 5-HT3 receptor.
2014,
Pubmed
Henderson,
Defining the putative inhibitory site for a selective negative allosteric modulator of human α4β2 neuronal nicotinic receptors.
2012,
Pubmed
Hibbs,
Principles of activation and permeation in an anion-selective Cys-loop receptor.
2011,
Pubmed
Jayakar,
Identification of propofol binding sites in a nicotinic acetylcholine receptor with a photoreactive propofol analog.
2013,
Pubmed
Jensen,
Neuronal nicotinic acetylcholine receptors: structural revelations, target identifications, and therapeutic inspirations.
2005,
Pubmed
Kim,
Synthesis of desformylflustrabromine and its evaluation as an alpha4beta2 and alpha7 nACh receptor modulator.
2007,
Pubmed
,
Xenbase
Labarca,
Channel gating governed symmetrically by conserved leucine residues in the M2 domain of nicotinic receptors.
1995,
Pubmed
,
Xenbase
Liu,
Positive allosteric modulation of α4β2 nicotinic acetylcholine receptors as a new approach to smoking reduction: evidence from a rat model of nicotine self-administration.
2013,
Pubmed
Ludwig,
Localization by site-directed mutagenesis of a galantamine binding site on α7 nicotinic acetylcholine receptor extracellular domain.
2010,
Pubmed
Mazzaferro,
Non-equivalent ligand selectivity of agonist sites in (α4β2)2α4 nicotinic acetylcholine receptors: a key determinant of agonist efficacy.
2014,
Pubmed
,
Xenbase
Middleton,
Photoaffinity labeling the torpedo nicotinic acetylcholine receptor with [(3)H]tetracaine, a nondesensitizing noncompetitive antagonist.
1999,
Pubmed
Middleton,
Mapping of the acetylcholine binding site of the nicotinic acetylcholine receptor: [3H]nicotine as an agonist photoaffinity label.
1991,
Pubmed
Miller,
Crystal structure of a human GABAA receptor.
2014,
Pubmed
Mnatsakanyan,
Experimental determination of the vertical alignment between the second and third transmembrane segments of muscle nicotinic acetylcholine receptors.
2013,
Pubmed
,
Xenbase
Nirthanan,
Identification of binding sites in the nicotinic acetylcholine receptor for TDBzl-etomidate, a photoreactive positive allosteric effector.
2008,
Pubmed
Olsen,
Structural and functional studies of the modulator NS9283 reveal agonist-like mechanism of action at α4β2 nicotinic acetylcholine receptors.
2014,
Pubmed
,
Xenbase
Oswald,
Multiple affinity states for noncompetitive blockers revealed by [3H]phencyclidine binding to acetylcholine receptor rich membrane fragments from Torpedo marmorata.
1983,
Pubmed
Pandya,
Allosteric modulator Desformylflustrabromine relieves the inhibition of α2β2 and α4β2 nicotinic acetylcholine receptors by β-amyloid(1-42) peptide.
2011,
Pubmed
,
Xenbase
Peters,
Four new bromotryptamine derivatives from the marine bryozoan Flustra foliacea.
2002,
Pubmed
,
Xenbase
Pratt,
Identification of sites of incorporation in the nicotinic acetylcholine receptor of a photoactivatible general anesthetic.
2000,
Pubmed
Richter,
Diazepam-bound GABAA receptor models identify new benzodiazepine binding-site ligands.
2012,
Pubmed
Sala,
Potentiation of human alpha4beta2 neuronal nicotinic receptors by a Flustra foliacea metabolite.
2005,
Pubmed
,
Xenbase
Schägger,
Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100 kDa.
1987,
Pubmed
Seo,
The positive allosteric modulator morantel binds at noncanonical subunit interfaces of neuronal nicotinic acetylcholine receptors.
2009,
Pubmed
,
Xenbase
Sigel,
The benzodiazepine binding site of GABAA receptors.
1997,
Pubmed
Taly,
Nicotinic receptors: allosteric transitions and therapeutic targets in the nervous system.
2009,
Pubmed
Unwin,
Refined structure of the nicotinic acetylcholine receptor at 4A resolution.
2005,
Pubmed
White,
Agonist-induced changes in the structure of the acetylcholine receptor M2 regions revealed by photoincorporation of an uncharged nicotinic noncompetitive antagonist.
1992,
Pubmed
White,
Photolabeling of membrane-bound Torpedo nicotinic acetylcholine receptor with the hydrophobic probe 3-trifluoromethyl-3-(m-[125I]iodophenyl)diazirine.
1988,
Pubmed
Williams,
Positive allosteric modulators as an approach to nicotinic acetylcholine receptor-targeted therapeutics: advantages and limitations.
2011,
Pubmed
Yamodo,
Conformational changes in the nicotinic acetylcholine receptor during gating and desensitization.
2010,
Pubmed
Young,
Potentiation of alpha7 nicotinic acetylcholine receptors via an allosteric transmembrane site.
2008,
Pubmed
,
Xenbase
Ziebell,
Identification of binding sites in the nicotinic acetylcholine receptor for [3H]azietomidate, a photoactivatable general anesthetic.
2004,
Pubmed