A mutant with bilateral whisker to barrel inputs unveils somatosensory mapping rules in the cerebral cortex
- Hôpital de la Pitié-Salpétrière, France
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, France
- University of Maryland School of Medicine, United States
- University of Konstanz, Germany
- Friedrich Miescher Institute for Biomedical Research, Switzerland
- INSERM, U839, Institut du Fer à Moulin, France
Abstract
In mammals, tactile information is mapped topographically onto the contralateral side of the brain in the primary somatosensory cortex (S1). Here we describe that in Robo3 mouse mutants a sizeable fraction of the trigemino-thalamic inputs project ipsilaterally rather than contralaterally. The resulting mixture of crossed and uncrossed sensory inputs creates bilateral whisker maps in the thalamus and cortex. Surprisingly, these maps are segregated resulting in a duplication of whisker representations and a doubling of the number of barrels without changes of the S1 size. Sensory deprivation shows competitive interactions between the ipsi/contralateral whisker maps. This study reveals that the somatosensory system can form a somatotopic map to integrate bilateral sensory inputs but organizes the maps in a different way than in the visual, or auditory systems. Therefore, while the molecular pre-patterning constrains their orientation and position, the preservation of the continuity of inputs defines the layout of the somatosensory maps.
Article and author information
Author details
Claudius F Kratochwil
Funding
Agence Nationale de la Recherche (ANR-08-MNP-030,ANR-08,MNP-032,ANR-14-CE13-0004-01,ANR-10-LABX-65)
- Filippo M Rijli
- Patricia Gaspar
- Alain Chédotal
Fondation pour la Recherche Médicale (DEQ20120323700)
- Alain Chédotal
National Institute of Neurological Disorders and Stroke (RO1 NS039050)
- Reha S Erzurumlu
swiss national science foundation (CRSI33_127440)
- Filippo M Rijli
Association Française contre les Myopathies
- Nicolas Renier
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 animal procedures were carried out in accordance to institutional guidelines and approved by the UPMC University ethic committee (ComitÃ{copyright, serif} Charles Darwin, authorization # 03787.02). All surgery was performed under ketamine/xylazine anesthesia, and every effort was made to minimize suffering.
Copyright
© 2017, Renier 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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A mutant with bilateral whisker to barrel inputs unveils somatosensory mapping rules in the cerebral cortex
eLife 6:e23494.
https://doi.org/10.7554/eLife.23494
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