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. Pentamer of two alpha chains, and one each of the beta, delta, and gamma (in immature muscle) or epsilon (in mature muscle) chains. At least in myotubes of skeletal muscle. Both short and long isoforms are found in a 17 days old embryo, whereas the short isoform is the only isoform present in the newborn muscle. Belongs to the ligand-gated ion channel (TC 1.A.9) family. Acetylcholine receptor (TC 1.A.9.1) subfamily. Gamma/CHRNG sub-subfamily.