Ankyrin-G regulates inactivation gating of the neuronal sodium channel, Nav1.6.

Published

Journal Article

Ankyrin-G, a modular protein, plays a critical role in clustering voltage-gated sodium channels (Nav channels) in nodes of Ranvier and initial segments of mammalian neurons. However, direct effects of ankyrin-G on electrophysiological properties of Nav channels remain elusive. In this study, we explored whether ankyrin-G has a role in modifying gating properties of the neuronal Nav1.6 channel that is predominantly localized at nodes of Ranvier and initial segments. TsA201 cells transfected with the human Nav1.6 cDNA alone exhibited significant persistent sodium current (Ina-p). On the other hand, Ina-p was barely detected on co-expression with ankyrin-G. Ankyrin-B, another ankyrin, did not show such an effect. Expression of chimeras between the two isoforms of ankyrin suggests that the membrane-binding domain of ankyrin-G is critical for reducing the Ina-p of Nav1.6. These results suggest that ankyrin-G regulates neuronal excitability not only through clustering Nav channels but also by directly modifying their channel gating.

Full Text

Duke Authors

Cited Authors

  • Shirahata, E; Iwasaki, H; Takagi, M; Lin, C; Bennett, V; Okamura, Y; Hayasaka, K

Published Date

  • September 2006

Published In

Volume / Issue

  • 96 / 3

Start / End Page

  • 1347 - 1357

PubMed ID

  • 16775201

Pubmed Central ID

  • 16775201

International Standard Serial Number (ISSN)

  • 0022-3077

Digital Object Identifier (DOI)

  • 10.1152/jn.01264.2005

Language

  • eng

Conference Location

  • United States