Axon sorting within the spinal cord marginal zone via Robo-mediated inhibition of N-cadherin controls spinocerebellar tract formation.
J Neurosci
; 32(44): 15377-87, 2012 Oct 31.
Article
em En
| MEDLINE
| ID: mdl-23115176
ABSTRACT
The axons of spinal projection neurons transmit sensory information to the brain by ascending within highly organized longitudinal tracts. However, the molecular mechanisms that control the sorting of these axons within the spinal cord and their directed growth to poorly defined targets are not understood. Here, we show that an interplay between Robo and the cell adhesion molecule, N-cadherin, sorts spinal commissural axons into appropriate longitudinal tracts within the spinal cord, and thereby facilitates their brain targeting. Specifically, we show that d1 and d2 spinal commissural axons join the lateral funiculus within the spinal cord and target the cerebellum in chick embryos, and that these axons contribute to the spinocerebellar projection in transgenic reporter mice. Disabling Robo signaling or overexpressing N-cadherin on these axons prevents the formation of the lateral funiculus and the spinocerebellar tract, and simultaneously perturbing Robo and N-cadherin function rescues both phenotypes in chick embryos. Consistent with these observations, disabling Robo function in conditional N-cadherin knock-out mice results in a wild-type-like lateral funiculus. Together, these findings suggest that spinal projection axons must be sorted into distinct longitudinal tracts within the spinal cord proper to project to their brain targets.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Medula Espinal
/
Axônios
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Receptores Imunológicos
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Caderinas
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Tratos Espinocerebelares
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Proteínas do Tecido Nervoso
Limite:
Animals
Idioma:
En
Revista:
J Neurosci
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos