Spinal premotor interneurons controlling antagonistic muscles are spatially intermingled

  1. Remi Ronzano
  2. Sophie Skarlatou
  3. Bianca K Barriga
  4. B Anne Bannatyne
  5. Gardave Singh Bhumbra
  6. Joshua D Foster
  7. Jeffrey D Moore
  8. Camille Lancelin
  9. Amanda M Pocratsky
  10. Mustafa Görkem Özyurt
  11. Calvin Chad Smith
  12. Andrew J Todd
  13. David J Maxwell
  14. Andrew J Murray
  15. Samuel L Pfaff  Is a corresponding author
  16. Robert M Brownstone  Is a corresponding author
  17. Niccolò Zampieri  Is a corresponding author
  18. Marco Beato  Is a corresponding author
  1. University College London, United Kingdom
  2. Max Delbrück Center for Molecular Medicine, Germany
  3. Salk Institute for Biological Studies, United States
  4. University of Glasgow, United Kingdom
  5. Howard Hughes Medical Institute, Harvard University, United States

Abstract

Elaborate behaviours are produced by tightly controlled flexor-extensor motor neuron activation patterns. Motor neurons are regulated by a network of interneurons within the spinal cord, but the computational processes involved in motor control are not fully understood. The neuroanatomical arrangement of motor and premotor neurons into topographic patterns related to their controlled muscles is thought to facilitate how information is processed by spinal circuits. Rabies retrograde monosynaptic tracing has been used to label premotor interneurons innervating specific motor neuron pools, with previous studies reporting topographic mediolateral positional biases in flexor and extensor premotor interneurons. To more precisely define how premotor interneurons contacting specific motor pools are organized, we used multiple complementary viral-tracing approaches in mice to minimize systematic biases associated with each method. Contrary to expectations, we found that premotor interneurons contacting motor pools controlling flexion and extension of the ankle are highly intermingled rather than segregated into specific domains like motor neurons. Thus, premotor spinal neurons controlling different muscles process motor instructions in the absence of clear spatial patterns among the flexor-extensor circuit components.

Data availability

All data generated during this study are included in the manuscript and supporting files. We also provide a link to two GitHub repositories: one includes the whole manuscript in a MATLAB executable format (requires a licence) that allows the reader to interact with the original plots and change the settings of the gaussian kernel used to represent the data. The second is a GitHub repository containing the R version of the manuscript

The following data sets were generated

Article and author information

Author details

  1. Remi Ronzano

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  2. Sophie Skarlatou

    Max Delbrück Center for Molecular Medicine, Berlin, Germany
    Competing interests
    No competing interests declared.
  3. Bianca K Barriga

    Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, United States
    Competing interests
    No competing interests declared.
  4. B Anne Bannatyne

    Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    No competing interests declared.
  5. Gardave Singh Bhumbra

    Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  6. Joshua D Foster

    Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  7. Jeffrey D Moore

    Department of Molecular and Cellular Biology, Howard Hughes Medical Institute, Harvard University, Cambridge, United States
    Competing interests
    No competing interests declared.
  8. Camille Lancelin

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  9. Amanda M Pocratsky

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  10. Mustafa Görkem Özyurt

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    Competing interests
    No competing interests declared.
  11. Calvin Chad Smith

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    Competing interests
    Calvin Chad Smith, is currently an employee of Sania therapeutics. His work is not related to that reported in this manuscript..
  12. Andrew J Todd

    Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3007-6749
  13. David J Maxwell

    Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    No competing interests declared.
  14. Andrew J Murray

    Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, London, United Kingdom
    Competing interests
    Andrew J Murray, is a co-founder of Sania Therapeutics. His work is not related to that reported in this manuscript. AM has founders stock in Sania Therapeutics, Ltd..
  15. Samuel L Pfaff

    Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, United States
    For correspondence
    pfaff@salk.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2142-166X
  16. Robert M Brownstone

    Department of Neuromuscular Diseases, University College London, London, United Kingdom
    For correspondence
    r.brownstone@ucl.ac.uk
    Competing interests
    Robert M Brownstone, has a grant from Medical Research Council, is a a co-founder of the parent company, Sania Therapeutics, Ltd. Work not related to that reported in this manuscript.RB is as an Associate Editor for Journal of Neurophysiology, has a patent (18 July, 2020, Priority patent GB 2010981.5; published 20 Jan, 2022, WO/2022/013396 Gene therapy for neuromuscular and neuromotor disorders") unrelated to this manuscript and is an unpaid Trustee for Stoke Mandeville Spinal Research.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5135-2725
  17. Niccolò Zampieri

    Max Delbrück Center for Molecular Medicine, Berlin, Germany
    For correspondence
    niccolo.zampieri@mdc-berlin.de
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2228-9453
  18. Marco Beato

    Department of Neuroscience Physiology and P, University College London, London, United Kingdom
    For correspondence
    m.beato@ucl.ac.uk
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7283-8318

Funding

Biotechnology and Biological Sciences Research Council (BB/L001454)

  • Andrew J Todd
  • David J Maxwell
  • Marco Beato

Marguerite Vogt Award

  • Bianca K Barriga

Brain Research UK

  • Robert M Brownstone

Deutsche Forschungsgemeinschaft (ZA 885/1-1)

  • Sophie Skarlatou
  • Niccolò Zampieri

Deutsche Forschungsgemeinschaft (EXC 257 NeuroCure)

  • Sophie Skarlatou
  • Niccolò Zampieri

Benjamin Lewis Chair in Neuroscience

  • Samuel L Pfaff

Sol Goldman Charitable Trust

  • Samuel L Pfaff

National Institute of health (1 U19 NS112959-01)

  • Samuel L Pfaff

National Institute of health (1 R01 NS123160-01)

  • Samuel L Pfaff

Wellcome Trust (225674/Z/22/Z)

  • Remi Ronzano

Biotechnology and Biological Sciences Research Council (BB/S005943/1)

  • Marco Beato

Leverhulme Trust (RPG-2013-176)

  • Marco Beato

Wellcome Trust (110193)

  • Robert M Brownstone

Jane Coffin Childs Memorial Fund for Medical Research

  • Jeffrey D Moore

Eunice Kennedy Shriver National Institute of Child Health and Human Development (5K99HD096512)

  • Jeffrey D Moore

University of California, San Diego (T32 GM007240)

  • Bianca K Barriga

Timken-Sturgis foundation

  • Bianca K Barriga

Salk Institute for Biological Studies

  • Bianca K Barriga

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

Reviewing Editor

  1. Jeffrey C Smith, National Institute of Neurological Disorders and Stroke, United States

Ethics

Animal experimentation: All experiments were performed in strict adherence to the Animals (Scientific Procedures) Act UK (1986) and certified by the UCL AWERB committee, under project licence number 70/9098. All experiments performed at the MDC were carried out in compliance with the German Animal Welfare Act and approved by the Regional Office for Health and Social Affairs Berlin (LAGeSo). All experiments performed at the Salk Institute were conducted in accordance with IACUC and AAALAC guidelines of the Salk Institute for Biological Studies. All surgeries were performed under general isofluorane anaesthesia. The mice were closely monitored for a 24-hr period following surgery to detect any sign of distress or motor impairment. Every effort was made to minimize suffering.

Version history

  1. Preprint posted: February 11, 2021 (view preprint)
  2. Received: July 19, 2022
  3. Accepted: December 11, 2022
  4. Accepted Manuscript published: December 13, 2022 (version 1)
  5. Accepted Manuscript updated: December 16, 2022 (version 2)
  6. Version of Record published: January 17, 2023 (version 3)

Copyright

© 2022, Ronzano et al.

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. Remi Ronzano
  2. Sophie Skarlatou
  3. Bianca K Barriga
  4. B Anne Bannatyne
  5. Gardave Singh Bhumbra
  6. Joshua D Foster
  7. Jeffrey D Moore
  8. Camille Lancelin
  9. Amanda M Pocratsky
  10. Mustafa Görkem Özyurt
  11. Calvin Chad Smith
  12. Andrew J Todd
  13. David J Maxwell
  14. Andrew J Murray
  15. Samuel L Pfaff
  16. Robert M Brownstone
  17. Niccolò Zampieri
  18. Marco Beato
(2022)
Spinal premotor interneurons controlling antagonistic muscles are spatially intermingled
eLife 11:e81976.
https://doi.org/10.7554/eLife.81976

Share this article

https://doi.org/10.7554/eLife.81976

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