Spinal lumbar dI2 interneurons contribute to stability of bipedal stepping
- IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, 91120, Israel, Israel
- Institut de recherches cliniques de Montréal (IRCM), Canada
- University of California, Irvine, United States
- Institute of Animal Science Poultry and Aquaculture Sci. Dept. Agricultural Research Organization, The Volcani Center, Israel, Israel
- Hebrew University, Israel
Abstract
Peripheral and intraspinal feedback is required to shape and update the output of spinal networks that execute motor behavior. We report that lumbar dI2 spinal interneurons in chicks receive synaptic input from afferents and premotor neurons. These interneurons innervate contralateral premotor networks in the lumbar and brachial spinal cord, and their ascending projections innervate the cerebellum. These findings suggest that dI2 neurons function as interneurons in local lumbar circuits, are involved in lumbo-brachial coupling, and that part of them deliver peripheral and intraspinal feedback to the cerebellum. Silencing of dI2 neurons leads to destabilized stepping in P8 hatchlings, with occasional collapses, variable step profiles and a wide-base walking gait, suggesting that dI2 neurons may contribute to the stabilization of the bipedal gait.
Data availability
All data generated or analysed during this study are included in the manuscript and the supporting files.
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Author details
Funding
Israel Science Foundation
- Avihu Klar
US Israel Binational Science Foundation BSF
- Avihu Klar
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 involved with animals were conducted in accordance with the designated Experiments in Animals Ethic Committee policies and under its approval.
Copyright
© 2021, Haimson 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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Spinal lumbar dI2 interneurons contribute to stability of bipedal stepping
eLife 10:e62001.
https://doi.org/10.7554/eLife.62001
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