RRC ID 40029
Author Yao C, Vanderpool KG, Delfiner M, Eddy V, Lucaci AG, Soto-Riveros C, Yasumura T, Rash JE, Pereda AE.
Title Electrical synaptic transmission in developing zebrafish: properties and molecular composition of gap junctions at a central auditory synapse.
Journal J Neurophysiol
Abstract In contrast to the knowledge of chemical synapses, little is known regarding the properties of gap junction-mediated electrical synapses in developing zebrafish, which provide a valuable model to study neural function at the systems level. Identifiable "mixed" (electrical and chemical) auditory synaptic contacts known as "club endings" on Mauthner cells (2 large reticulospinal neurons involved in tail-flip escape responses) allow exploration of electrical transmission in fish. Here, we show that paralleling the development of auditory responses, electrical synapses at these contacts become anatomically identifiable at day 3 postfertilization, reaching a number of ∼6 between days 4 and 9. Furthermore, each terminal contains ∼18 gap junctions, representing between 2,000 and 3,000 connexon channels formed by the teleost homologs of mammalian connexin 36. Electrophysiological recordings revealed that gap junctions at each of these contacts are functional and that synaptic transmission has properties that are comparable with those of adult fish. Thus a surprisingly small number of mixed synapses are responsible for the acquisition of auditory responses by the Mauthner cells, and these are likely sufficient to support escape behaviors at early developmental stages.
Volume 112(9)
Pages 2102-13
Published 2014-11-1
DOI 10.1152/jn.00397.2014
PII jn.00397.2014
PMID 25080573
PMC PMC4274921
MeSH Animals Auditory Pathways / growth & development Auditory Pathways / physiology Connexins / genetics Connexins / metabolism Electrical Synapses / physiology* Gap Junctions / metabolism Gap Junctions / physiology* Larva / growth & development Larva / physiology Rhombencephalon / growth & development Rhombencephalon / physiology* Synaptic Transmission* Zebrafish
IF 2.234
Times Cited 13
Zebrafish Tol-056