Neuronal nicotinic acetylcholine receptor subunit beta-2 (CHRNB2)

The Neuronal nicotinic acetylcholine receptor subunit beta-2 (CHRNB2) is a fundamental component of heteromeric nicotinic receptors in the mammalian brain, where it most frequently assembles with the alpha-4 subunit to form the high-affinity alpha-4-beta-2 (α4β2) receptor subtype (UniProt: P17671). These pentameric ligand-gated ion channels are essential for mediating fast excitatory neurotransmission and modulating the release of key neurotransmitters such as dopamine, which is central to the brain's reward system (PubMed: 11218765). Because of its role in dopamine modulation, the beta-2 subunit is a primary target for smoking cessation pharmacotherapies like varenicline, which acts as a partial agonist to reduce nicotine cravings and withdrawal symptoms. Mutations in the CHRNB2 gene are clinically linked to Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE), a condition characterized by clusters of brief motor seizures during sleep (NCBI Gene: 1141). Furthermore, the subunit is implicated in the pathophysiology of neurodegenerative diseases and cognitive dysfunction, making it a focus for the development of cognitive enhancers and neuroprotective agents (PubMed: 22432014).

Other names

Cholinergic receptor nicotinic beta 2 subunitnAChR subunit beta-2Acetylcholine receptor subunit beta-2EFNL3

Drugs targeting this subunit typically act as agonists, partial agonists, or antagonists at the interface of heteromeric pentamers (most commonly the α4β2 subtype). Binding induces a conformational change that opens a central ion-conducting pore, allowing the influx of sodium (Na+) and calcium (Ca2+) ions, which leads to neuronal depolarization and the subsequent release of various neurotransmitters like dopamine and glutamate (PubMed: 17030507, NCBI Gene: 1141).