Nodal ß spectrins are required to maintain Na+ channel clustering and axon integrity.
Elife
; 92020 02 13.
Article
en En
| MEDLINE
| ID: mdl-32052742
ABSTRACT
Clustered ion channels at nodes of Ranvier are critical for fast action potential propagation in myelinated axons. Axon-glia interactions converge on ankyrin and spectrin cytoskeletal proteins to cluster nodal Na+ channels during development. However, how nodal ion channel clusters are maintained is poorly understood. Here, we generated mice lacking nodal spectrins in peripheral sensory neurons to uncouple their nodal functions from their axon initial segment functions. We demonstrate a hierarchy of nodal spectrins, where ß4 spectrin is the primary spectrin and ß1 spectrin can substitute; each is sufficient for proper node organization. Remarkably, mice lacking nodal ß spectrins have normal nodal Na+ channel clustering during development, but progressively lose Na+ channels with increasing age. Loss of nodal spectrins is accompanied by an axon injury response and axon deformation. Thus, nodal spectrins are required to maintain nodal Na+ channel clusters and the structural integrity of axons.
Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Nódulos de Ranvier
/
Canales de Sodio
/
Espectrina
Límite:
Animals
Idioma:
En
Revista:
Elife
Año:
2020
Tipo del documento:
Article
País de afiliación:
Estados Unidos