Functional diversity of excitatory commissural interneurons in adult zebrafish

  1. E Rebecka Björnfors
  2. Abdel El Manira  Is a corresponding author
  1. Karolinska Institute, Sweden

Abstract

Flexibility in the bilateral coordination of muscle contraction underpins variable locomotor movements or gaits. While the locomotor rhythm is generated by ipsilateral excitatory interneurons, less is known about the commissural excitatory interneurons. Here we examined how the activity of the V0v interneurons - an important commissural neuronal class - varies with the locomotor speed in adult zebrafish. Although V0v interneurons are molecularly homogenous, their activity pattern during locomotion is not uniform. They consist of two distinct types dependent on whether they display rhythmicity or not during locomotion. The rhythmic V0v interneurons were further subdivided into three sub-classes engaged sequentially, first at slow then intermediate and finally fast locomotor speeds. Their order of recruitment is defined by scaling their synaptic current with their input resistance. Thus we uncover, in an adult vertebrate, a novel organizational principle for a key class of commissural interneurons and their recruitment pattern as a function of locomotor speed.

Article and author information

Author details

  1. E Rebecka Björnfors

    Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
    Competing interests
    The authors declare that no competing interests exist.
  2. Abdel El Manira

    Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
    For correspondence
    Abdel.Elmanira@ki.se
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5920-9384

Funding

Karolinska Institutet

  • Abdel El Manira

Hjärnfonden

  • Abdel El Manira

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

Ethics

Animal experimentation: All experimental protocols were approved by the local Animal Research Ethical Committee, Stockholm (Stockholms Norra Djurförsöksetiska Nämnd). Protocol number N122/13.

Copyright

© 2016, Björnfors & El Manira

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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  1. E Rebecka Björnfors
  2. Abdel El Manira
(2016)
Functional diversity of excitatory commissural interneurons in adult zebrafish
eLife 5:e18579.
https://doi.org/10.7554/eLife.18579

Share this article

https://doi.org/10.7554/eLife.18579

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