Developmental effects of nonuniform acetylcholine receptor expression on motor neuron and synapse morphology in larval zebrafish

It is well established that altered postsynaptic receptor activity leads to changes in presynaptic transmission and presynaptic connectivity throughout the nervous system. Receptor-activity-dependent modulation of presynaptic transmission, termed "synaptic plasticity", was first highlighted from studies at neuromuscular synapses and later recapitulated at central synapses. The receptor-activity-dependent process responsible for reducing the number of presynaptic inputs from multiple neurons onto a target cell throughout synapse development, a form of synaptic competition, was also first demonstrated at the neuromuscular junction (NMJ) and later observed at central synapses. This study, however, probes for evidence of receptor-activity-dependent intra-neuronal competition between axon terminals from the same motor neuron.