Axonal neurofilaments control multiple fiber properties but do not influence structure or spacing of nodes of Ranvier.


Journal Article

In the vertebrate nervous system, axon calibers correlate positively with myelin sheath dimensions and electrophysiological parameters including action potential amplitude and conduction velocity. Neurofilaments, a prominent component of the neuronal cytoskeleton, are required by axons to support their normal radial growth. To distinguish between fiber features that arise in response to absolute axon caliber and those that are under autonomous control, we investigated transgenic mice in which neurofilaments are sequestered in neuronal cell bodies. The neurofilament deficient axons in such mice achieve mature calibers only 50% of normal and have altered conduction properties. We show here that this primary axonal defect also induces multiple changes in myelin sheath composition and radial dimensions. Remarkably, other fundamental fiber features, including internodal spacing and the architecture and composition of nodes of Ranvier, remain unaltered. Thus, many fiber characteristics are controlled through mechanisms operating independently of absolute axon caliber and the neurofilament cytoskeleton.

Full Text

Cited Authors

  • Perrot, R; Lonchampt, P; Peterson, AC; Eyer, J

Published Date

  • September 2007

Published In

Volume / Issue

  • 27 / 36

Start / End Page

  • 9573 - 9584

PubMed ID

  • 17804618

Pubmed Central ID

  • 17804618

Electronic International Standard Serial Number (EISSN)

  • 1529-2401

International Standard Serial Number (ISSN)

  • 0270-6474

Digital Object Identifier (DOI)

  • 10.1523/jneurosci.1224-07.2007


  • eng