RRC ID 64798
Author Zempo B, Yamamoto Y, Williams T, Ono F.
Title Synaptic silencing of fast muscle is compensated by rewired innervation of slow muscle.
Journal Sci Adv
Abstract For decades, numerous studies have proposed that fast muscles contribute to quick movement, while slow muscles underlie locomotion requiring endurance. By generating mutant zebrafish whose fast muscles are synaptically silenced, we examined the contribution of fast muscles in both larval and adult zebrafish. In the larval stage, mutants lacked the characteristic startle response to tactile stimuli: bending of the trunk (C-bend) followed by robust forward propulsion. Unexpectedly, adult mutants with silenced fast muscles showed robust C-bends and forward propulsion upon stimulation. Retrograde labeling revealed that motor neurons genetically programmed to form synapses on fast muscles are instead rerouted and innervate slow muscles, which led to partial conversion of slow and intermediate muscles to fast muscles. Thus, extended silencing of fast muscle synapses changed motor neuron innervation and caused muscle cell type conversion, revealing an unexpected mechanism of locomotory adaptation.
Volume 6(15)
Pages eaax8382
Published 2020-4-1
DOI 10.1126/sciadv.aax8382
PII aax8382
PMID 32284992
PMC PMC7141830
MeSH Animals Animals, Genetically Modified Gene Knockdown Techniques Gene Targeting Genetic Loci Larva Locomotion Muscle Fibers, Fast-Twitch / physiology* Muscle Fibers, Slow-Twitch / physiology* Neuromuscular Junction / physiology* Receptors, Nicotinic / deficiency Synaptic Transmission Zebrafish
IF 13.117
Zebrafish RIKEN WT