1. Neuroscience
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Multiple conserved cell adhesion protein interactions mediate neural wiring of a sensory circuit in C. elegans

  1. Byunghyuk Kim  Is a corresponding author
  2. Scott W Emmons  Is a corresponding author
  1. Albert Einstein College of Medicine, United States
Research Article
  • Cited 16
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Cite this article as: eLife 2017;6:e29257 doi: 10.7554/eLife.29257


Nervous system function relies on precise synaptic connections. A number of widely-conserved cell adhesion proteins are implicated in cell recognition between synaptic partners, but how these proteins act as a group to specify a complex neural network is poorly understood. Taking advantage of known connectivity in C. elegans, we identified and studied cell adhesion genes expressed in three interacting neurons in the mating circuits of the adult male. Two interacting pairs of cell surface proteins independently promote fasciculation between sensory neuron HOA and its postsynaptic target interneuron AVG: BAM-2/neurexin-related in HOA binds to CASY-1/calsyntenin in AVG; SAX-7/L1CAM in sensory neuron PHC binds to RIG-6/contactin in AVG. A third, basal pathway results in considerable HOA-AVG fasciculation and synapse formation in the absence of the other two. The features of this multiplexed mechanism help to explain how complex connectivity is encoded and robustly established during nervous system development.

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Author details

  1. Byunghyuk Kim

    Department of Genetics, Albert Einstein College of Medicine, Bronx, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7967-7406
  2. Scott W Emmons

    Department of Genetics, Albert Einstein College of Medicine, Bronx, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.


National Institutes of Health (R01 GM066897 and R01 MH112689)

  • Scott W Emmons

G Harold and Leila Y. Mathers Foundation

  • Scott W Emmons

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Oliver Hobert, Howard Hughes Medical Institute, Columbia University, United States

Publication history

  1. Received: June 4, 2017
  2. Accepted: September 8, 2017
  3. Accepted Manuscript published: September 13, 2017 (version 1)
  4. Version of Record published: September 28, 2017 (version 2)


© 2017, Kim & Emmons

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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