Nicotinic Acetylcholine Receptor Alpha4 Subunit (nAChRα4)

The nicotinic acetylcholine receptor alpha4 subunit (nAChRα4) is a protein encoded by the CHRNA4 gene in humans. It is a critical subunit of nicotinic acetylcholine receptors (nAChRs), which are ligand-gated ion channels that mediate fast signal transmission at synapses. The most common configuration in the brain consists of two alpha4 (α4) subunits and three beta2 (β2) subunits, forming the α4β2 receptor, which exists in two distinct stoichiometries with varying nicotine sensitivities and calcium permeabilities. The alpha4 subunit can also combine with beta4 subunits. Upon binding to acetylcholine or nicotine, the receptor undergoes a conformational change, opening an ion-conducting channel across the plasma membrane, allowing ions like calcium, sodium, and potassium to cross the cell membrane. Alpha4-containing nAChRs play a crucial role in nicotine addiction, learning, attention, and growth hormone secretion. They are implicated in epilepsy, movement disorders, and cardiovascular conditions, making them therapeutic targets for smoking cessation, cognitive disorders, epilepsy, and movement disorders.

Other names

CHRNA4Nicotinic receptor subunit alpha-4Alpha4 subunit of nicotinic acetylcholine receptor

Agonist binding leading to ion channel opening and ion flux across the cell membrane.