overlaps overlaps motor neuron muscle cell neuromuscular junction NIF_Subcellular:sao1124888485 cellular_component Wikipedia:Neuromuscular_junction GO:0031594 The junction between the axon of a motor neuron and a muscle fiber. In response to the arrival of action potentials, the presynaptic button releases molecules of neurotransmitters into the synaptic cleft. These diffuse across the cleft and transmit the signal to the postsynaptic membrane of the muscle fiber, leading to a change in post-synaptic potential. synapse