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Structure and function of gap junctions in the developing brain

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Abstract

Gap-junction-dependent neuronal communication is widespread in the developing brain, and the prevalence of gap-junctional coupling is well correlated with specific developmental events. We summarize here our current knowledge of the contribution of gap junctions to brain development and propose that they carry out this role by taking advantage of the full complement of their functional properties. Thus, hemichannel activation may represent a key step in the initiation of Ca2+ waves that coordinate cell cycle events during early prenatal neurogenesis, whereas both hemichannels and/or gap junctions may control the division and migration of cohorts of precusor cells during late prenatal neurogenesis. Finally, the recent discovery that pannexins, a novel group of proteins prominently expressed in the brain, are able to form both hemichannels and gap-junction channels suggests that we need to seek more than just connexins with respect to these junctions.

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Fig. 1

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Correspondence to Rolf Dermietzel.

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Work in the authors’ laboratories is supported by the Deutsche Forschungsgemeinschaft, SFB 509 (R.D.) and by the Institut Pasteur (R.B.).

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Bruzzone, R., Dermietzel, R. Structure and function of gap junctions in the developing brain. Cell Tissue Res 326, 239–248 (2006). https://doi.org/10.1007/s00441-006-0287-0

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Keywords

  • Gap junction
  • Brain development
  • Prenatal neurogenesis
  • Pannexins
  • Hemichannels