CHRNB1

The muscle acetylcholine receptor is composed of five subunits: two alpha subunits and one beta, one gamma, and one delta subunit. This gene encodes the beta subunit of the acetylcholine receptor. The acetylcholine receptor changes conformation upon acetylcholine binding leading to the opening of an ion-conducting channel across the plasma membrane. Mutations in this gene are associated with slow-channel congenital myasthenic syndrome. [provided by RefSeq, Jul 2008]

Cholinergic Receptor Nicotinic Beta 1 Subunit

After binding acetylcholine, the AChR responds by an extensive change in conformation that affects all subunits and leads to opening of an ion-conducting channel across the plasma membrane.

Behavioral response to nicotine Source: UniProtKB
Cation transport Source: UniProtKB
Chemical synaptic transmission Source: GO_Central
Ion transmembrane transport Source: GO_Central
Muscle contraction Source: UniProtKB
Muscle fiber development Source: UniProtKB
Nervous system process Source: UniProtKB
Neuromuscular synaptic transmission Source: UniProtKB
Postsynaptic membrane organization Source: UniProtKB
Regulation of membrane potential Source: UniProtKB
Signal transduction Source: UniProtKB
Skeletal muscle contraction Source: Ensembl
Synaptic transmission, cholinergic Source: UniProtKB

Postsynaptic cell membrane; Cell membrane

Myasthenic syndrome, congenital, 2A, slow-channel (CMS2A): A form of congenital myasthenic syndrome, a group of disorders characterized by failure of neuromuscular transmission, including pre-synaptic, synaptic, and post-synaptic disorders that are not of autoimmune origin. Clinical features are easy fatigability and muscle weakness affecting the axial and limb muscles (with hypotonia in early-onset forms), the ocular muscles (leading to ptosis and ophthalmoplegia), and the facial and bulbar musculature (affecting sucking and swallowing, and leading to dysphonia). The symptoms fluctuate and worsen with physical effort. CMS2A is a slow-channel myasthenic syndrome. It is caused by kinetic abnormalities of the AChR, resulting in prolonged AChR channel opening episodes, prolonged endplate currents, and depolarization block. This is associated with calcium overload, which may contribute to subsequent degeneration of the endplate and postsynaptic membrane.
Myasthenic syndrome, congenital, 2C, associated with acetylcholine receptor deficiency (CMS2C): A form of congenital myasthenic syndrome, a group of disorders characterized by failure of neuromuscular transmission, including pre-synaptic, synaptic, and post-synaptic disorders that are not of autoimmune origin. Clinical features are easy fatigability and muscle weakness affecting the axial and limb muscles (with hypotonia in early-onset forms), the ocular muscles (leading to ptosis and ophthalmoplegia), and the facial and bulbar musculature (affecting sucking and swallowing, and leading to dysphonia). The symptoms fluctuate and worsen with physical effort. CMS2C is an autosomal recessive disorder of postsynaptic neuromuscular transmission, due to deficiency of AChR at the endplate that results in low amplitude of the miniature endplate potential and current. CMS2C is clinically characterized by early-onset muscle weakness with variable severity.

Extracellular: 24-244
Helical: 245-269
Helical: 277-295
Helical: 311-332
Cytoplasmic: 333-469
Helical: 470-488