The nicotinic acetylcholine receptor as a molecular machine for neuromuscular transmission

Abstract

The nicotinic acetylcholine receptor (nAChR) has crucial functions at the neuromuscular junction (NMJ). It belongs to the superfamily of pentameric ligand-gated ion channels and has become the stereotype for probing fundamental structures and mechanisms. The nAChR operates as a molecular machine that transduces the binding of nerve-released ACh into an electrical signal that initiates the process of muscle contraction. Its molecular design has been tuned to function as a near perfect on–off switch that responds to ACh with the efficiency and speed required for proper muscle function. Biochemical, biophysical, electrophysiological and structural studies have allowed an integrated description of the muscle nAChR, providing information of its molecular function at the NMJ in health and disease states and guiding rational therapy.