PUBLICATION

Gap-junction-mediated bioelectric signaling required for slow muscle development and function in zebrafish

Authors
Lukowicz-Bedford, R.M., Eisen, J.S., Miller, A.C.
ID
ZDB-PUB-240628-3
Date
2024
Source
Current biology : CB   34(14): 3116-3132.e5 (Journal)
Registered Authors
Eisen, Judith S., Miller, Adam
Keywords
Zebrafish, bioelectricity, connexin, development, gap junction, gjd4, neuromuscular
MeSH Terms
  • Animals
  • Connexins*/genetics
  • Connexins*/metabolism
  • Gap Junctions*/metabolism
  • Muscle Development
  • Signal Transduction*
  • Zebrafish*/embryology
  • Zebrafish Proteins*/genetics
  • Zebrafish Proteins*/metabolism
PubMed
38936363 Full text @ Curr. Biol.
Abstract
Bioelectric signaling, intercellular communication facilitated by membrane potential and electrochemical coupling, is emerging as a key regulator of animal development. Gap junction (GJ) channels can mediate bioelectric signaling by creating a fast, direct pathway between cells for the movement of ions and other small molecules. In vertebrates, GJ channels are formed by a highly conserved transmembrane protein family called the connexins. The connexin gene family is large and complex, creating challenges in identifying specific connexins that create channels within developing and mature tissues. Using the embryonic zebrafish neuromuscular system as a model, we identify a connexin conserved across vertebrate lineages, gjd4, which encodes the Cx46.8 protein, that mediates bioelectric signaling required for slow muscle development and function. Through mutant analysis and in vivo imaging, we show that gjd4/Cx46.8 creates GJ channels specifically in developing slow muscle cells. Using genetics, pharmacology, and calcium imaging, we find that spinal-cord-generated neural activity is transmitted to developing slow muscle cells, and synchronized activity spreads via gjd4/Cx46.8 GJ channels. Finally, we show that bioelectrical signal propagation within the developing neuromuscular system is required for appropriate myofiber organization and that disruption leads to defects in behavior. Our work reveals a molecular basis for GJ communication among developing muscle cells and reveals how perturbations to bioelectric signaling in the neuromuscular system may contribute to developmental myopathies. Moreover, this work underscores a critical motif of signal propagation between organ systems and highlights the pivotal role of GJ communication in coordinating bioelectric signaling during development.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping