RT Journal Article
SR Electronic
T1 Human <em>α</em>6<em>β</em>4 Nicotinic Acetylcholine Receptor: Heterologous Expression and Agonist Behavior Provide Insights into the Immediate Binding Site
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 339
OP 347
DO 10.1124/molpharm.123.000672
VO 103
IS 6
A1 María Constanza Maldifassi
A1 Hugo Rego Campello
A1 Timothy Gallagher
A1 Henry A. Lester
A1 Dennis A. Dougherty
YR 2023
UL http://molpharm.aspetjournals.org/content/103/6/339.abstract
AB Study of α6β4 nicotinic acetylcholine receptors (nAChRs) as a pharmacological target has recently gained interest because of their involvement in analgesia, control of catecholamine secretion, dopaminergic pathways, and aversive pathways. However, an extensive characterization of the human α6β4 nAChRs has been vitiated by technical difficulties resulting in poor receptor expression. In 2020, Knowland and collaborators identified BARP (β-anchoring and regulatory protein), a previously known voltage-gated calcium channel suppressor, as a novel human α6β4 chaperone. Here, we establish that co-expression of human BARP with human α6β4 in Xenopus oocytes, resulted in the functional expression of human α6β4 receptors with acetylcholine-elicited currents that allow an in-depth characterization of the receptor using two electrode voltage-clamp electrophysiology together with diverse agonists and receptor mutations. We report: 1) an extended pharmacological characterization of the receptor, and 2) key residues for agonist-activity located in or near the first shell of the binding pocket.SIGNIFICANCE STATEMENT The human α6β4 nicotinic acetylcholine receptor has attained increased interest because of its involvement in diverse physiological processes and diseases. Although recognized as a pharmacological target, development of specific agonists has been hampered by limited knowledge of its structural characteristics and by challenges in expressing the receptor. By including the chaperone β-anchoring and regulatory protein for enhanced expression and employing different ligands, we have studied the pharmacology of α6β4, providing insight into receptor residues and structural requirements for ligands important to consider for agonist-induced activation.