An innexin-dependent cell network establishes left-right neuronal asymmetry in C. elegans

Cell. 2007 May 18;129(4):787-99. doi: 10.1016/j.cell.2007.02.052.


Gap junctions are widespread in immature neuronal circuits, but their functional significance is poorly understood. We show here that a transient network formed by the innexin gap-junction protein NSY-5 coordinates left-right asymmetry in the developing nervous system of Caenorhabditis elegans. nsy-5 is required for the left and right AWC olfactory neurons to establish stochastic, asymmetric patterns of gene expression during embryogenesis. nsy-5-dependent gap junctions in the embryo transiently connect the AWC cell bodies with those of numerous other neurons. Both AWCs and several other classes of nsy-5-expressing neurons participate in signaling that coordinates left-right AWC asymmetry. The right AWC can respond to nsy-5 directly, but the left AWC requires nsy-5 function in multiple cells of the network. NSY-5 forms hemichannels and intercellular gap-junction channels in Xenopus oocytes, consistent with a combination of cell-intrinsic and network functions. These results provide insight into gap-junction activity in developing circuits.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Body Patterning / physiology*
  • Caenorhabditis elegans / embryology*
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans / ultrastructure
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / isolation & purification
  • Caenorhabditis elegans Proteins / metabolism*
  • Calcium Signaling / physiology
  • Cell Communication / physiology
  • Cell Differentiation / physiology
  • Connexins / genetics
  • Connexins / isolation & purification
  • Connexins / metabolism*
  • Functional Laterality / physiology
  • Gap Junctions / metabolism
  • Membrane Proteins / metabolism
  • Molecular Sequence Data
  • Nerve Net / embryology*
  • Nerve Net / metabolism
  • Nerve Net / ultrastructure
  • Nervous System / embryology*
  • Nervous System / metabolism
  • Nervous System / ultrastructure
  • Neurons / metabolism*
  • Neurons / ultrastructure
  • Olfactory Pathways / embryology
  • Olfactory Pathways / metabolism
  • Olfactory Pathways / ultrastructure


  • Caenorhabditis elegans Proteins
  • Connexins
  • Membrane Proteins
  • inx-19 protein, C elegans
  • unc-2 protein, C elegans