NMDA receptors control development of somatosensory callosal axonal projections
- University of California, San Francisco, United States
Abstract
Callosal projections from primary somatosensory cortex (S1) are key for processing somatosensory inputs and integrating sensory-motor information. How the callosal innervation pattern in S1 is formed during early postnatal development is not clear. We found that the normal termination pattern of these callosal projections is disrupted in cortex specific NMDAR mutants. Rather than projecting selectively to the primary/secondary somatosensory cortex (S1/S2) border, axons were uniformly distributed throughout S1. In addition, the density of this projection increased over postnatal life until the mice died by P30. By combining genetic and antibody-mediated loss of function, we demonstrated that it is GluN2B-containing NMDA receptors in target S1 that mediate this guidance phenotype, thus playing a central role in interhemispheric connectivity. Furthermore, we found that this function of NMDA receptors in callosal circuit formation is independent of ion channel function and works with the EPHRIN-B/EPHB system. Thus, NMDAR in target S1 cortex regulates the formation callosal circuits perhaps by modulating EPH-dependent repulsion.
Data availability
All data generated or analyses during this study are included in the manuscript.
Article and author information
Author details
Jeffrey Ohmann Bush
Funding
National Institute of Mental Health (R01MH119435)
- Jing Zhou
- Yong Lin
- Trung Huynh
- Hirofumi Noguchi
- Samuel Pleasure
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (AN176415) of the University of California San Francisco.
Copyright
© 2021, Zhou 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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NMDA receptors control development of somatosensory callosal axonal projections
eLife 10:e59612.
https://doi.org/10.7554/eLife.59612
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