A Speculative Model of AChR Gating at the Frog Neuromuscular Junction

Abstract

The animation depicts a speculative model of nicotinic acetylcholine receptor (AChR) gating at the frog neuromuscular junction. Following a nerve impulse, the neurotransmitter acetylcholine (ACh) is released from synaptic vesicles docked at the active zone of the presynaptic nerve terminal. ACh diffuses across the synaptic cleft to bind to AChRs, ligand-gated channels found at the lips of the postjunctional folds of the muscle, initiating gating, a conformational change that allows ions to flow through the channel and thereby elicit an electrical response in the muscle (the end-plate potential). In the AChR, gating involves a series of small conformational changes that propagate throughout the channel as it moves from "closed" to "open," rather than a synchronous switch in protein configuration. [ Resource Details ]