Chronology-based architecture of descending circuits that underlie the development of locomotor repertoire after birth

  1. Avinash Pujala
  2. Minoru Koyama  Is a corresponding author
  1. Janelia Research Campus, Howard Hughes Medical Institute, United States

Abstract

The emergence of new and increasingly sophisticated behaviors after birth is accompanied by dramatic increase of newly established synaptic connections in the nervous system. Little is known, however, of how nascent connections are organized to support such new behaviors alongside existing ones. To understand this, in the larval zebrafish we examined the development of spinal pathways from hindbrain V2a neurons and the role of these pathways in the development of locomotion. We found that new projections are continually layered laterally to existing neuropil, and give rise to distinct pathways that function in parallel to existing pathways. Across these chronologically layered pathways, the connectivity patterns and biophysical properties vary systematically to support a behavioral repertoire with a wide range of kinematics and dynamics. Such layering of new parallel circuits equipped with systematically changing properties may be central to the postnatal diversification and increasing sophistication of an animal's behavioral repertoire.

Data availability

Source data files have been provided for numerical data that are represented as graphs in Figure 3C, 7D, 7E, 7F, 8E, 9J, 9K, 9L, and 10C.

Article and author information

Author details

  1. Avinash Pujala

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8758-1634
  2. Minoru Koyama

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    koyamam@janelia.hhmi.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9774-9223

Funding

Howard Hughes Medical Institute

  • Avinash Pujala
  • Minoru Koyama

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 experiments presented in this study were conducted in accordance with the animal research guidelines from the National Institutes of Health and were approved by the Institutional Animal Care and Use Committee and Institutional Biosafety Committee of Janelia Research Campus. (16-145).

Reviewing Editor

  1. Vatsala Thirumalai, National Centre for Biological Sciences, India

Publication history

  1. Received: September 20, 2018
  2. Accepted: February 22, 2019
  3. Accepted Manuscript published: February 25, 2019 (version 1)
  4. Version of Record published: April 4, 2019 (version 2)

Copyright

© 2019, Pujala & Koyama

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. Avinash Pujala
  2. Minoru Koyama
(2019)
Chronology-based architecture of descending circuits that underlie the development of locomotor repertoire after birth
eLife 8:e42135.
https://doi.org/10.7554/eLife.42135

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