CHRNA1

The muscle acetylcholine receptor consiststs of 5 subunits of 4 different types: 2 alpha isoforms and 1 each of beta, gamma, and delta subunits.2 This gene encodes an alpha subunit that plays a role in acetlycholine binding/channel gating. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq]

cholinergic receptor, nicotinic, alpha 1 (muscle)

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.

Chemical synaptic transmission Source: GO_Central
Ion transmembrane transport Source: GO_Central
Muscle cell cellular homeostasis Source: BHF-UCL
Musculoskeletal movement Source: BHF-UCL
Nervous system process Source: GO_Central
Neuromuscular junction development Source: MGI
Neuromuscular process Source: BHF-UCL
Neuromuscular synaptic transmission Source: MGI
Neuronal action potential Source: BHF-UCL
Neuron cellular homeostasis Source: BHF-UCL
Regulation of membrane potential Source: BHF-UCL
Signal transduction Source: GO_Central
Skeletal muscle contraction Source: BHF-UCL
Skeletal muscle tissue growth Source: BHF-UCL

Postsynaptic cell membrane; Cell membrane

Multiple pterygium syndrome, lethal type (LMPS): Multiple pterygia are found infrequently in children with arthrogryposis and in fetuses with fetal akinesia syndrome. In lethal multiple pterygium syndrome there is intrauterine growth retardation, multiple pterygia, and flexion contractures causing severe arthrogryposis and fetal akinesia. Subcutaneous edema can be severe, causing fetal hydrops with cystic hygroma and lung hypoplasia. Oligohydramnios and facial anomalies are frequent. The alpha subunit is the main focus for antibody binding in myasthenia gravis. Myasthenia gravis is characterized by sporadic muscular fatigability and weakness, occurring chiefly in muscles innervated by cranial nerves, and characteristically improved by cholinesterase-inhibiting drugs.
Myasthenic syndrome, congenital, 1A, slow-channel (CMS1A): A common congenital myasthenic syndrome. Congenital myasthenic syndromes are characterized by 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. CMS1A 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, 1B, fast-channel (CMS1B): 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. CMS1B is a fast-channel myasthenic syndrome. It is caused by kinetic abnormalities of the AChR, resulting in brief opening and activity of the channel, with a rapid decay in endplate current, failure to achieve threshold depolarization of the endplate and consequent failure to fire an action potential.

Extracellular: 21-255
Helical: 256-280
Helical: 288-306
Helical: 322-341
Cytoplasmic: 342-453
Helical: 454-472