Neuronal nicotinic acetylcholine receptors (nAChRs) belong to the superfamily of ligand-gated ion channels and are widely expressed throughout the central and peripheral nervous systems. nAChRs play crucial roles in modulating a wide range of higher cognitive functions by mediating presynaptic, postsynaptic, and extrasynaptic signaling¹.

nAChRs are formed by the assembly of five transmembrane subunits, selected from a pool of 17 homologous polypeptides (α1-10, β1-4, γ, δ, and ε). There are many nAChR subtypes, each consisting of a specific combination of subunits, which mediate diverse physiological functions. They are widely expressed in the central nervous system, while, in the periphery, they mediate synaptic transmission at the neuromuscular junction and ganglia. nAChRs are also found in non-neuronal/non-muscle cells (keratinocytes, epithelia, macrophages, etc.)². Structurally, all subunits have the following: a conserved large extracellular N-terminal domain, three conserved transmembrane domains, a variable cytoplasmic loop and a fourth transmembrane domain with a short extracellular C-terminal domain. An active nAChR is generally a heteropentamer of these various subunits organized around a central pore³.

While most β subunits are neuronal, the β1 subunit forms functional receptors along with other subunits in the muscle². β1 subunit seems to be involved in myasthenia gravis (MG)⁴, an acquired autoimmune disease usually characterized by the presence of circulating autoantibodies that bind to and destroy muscle nAChRs⁵.