Ankyrin-based subcellular gradient of neurofascin, an immunoglobulin family protein, directs GABAergic innervation at purkinje axon initial segment.

Journal Article (Journal Article)

Distinct classes of GABAergic synapses are segregated into subcellular domains (i.e., dendrite, soma, and axon initial segment-AIS), thereby differentially regulating the input, integration, and output of principal neurons. In cerebellum, for example, basket interneurons make exquisitely precise "pinceau synapses" on AIS of Purkinje neurons, but the underlying mechanism is unknown. Using BAC transgenic reporter mice, we found that basket axons always contacted Purkinje soma before innervating AIS. This synapse targeting process followed the establishment of a subcellular gradient of neurofascin186 (NF186), an L1 family immunoglobulin cell adhesion molecule (L1CAM), along the Purkinje AIS-soma axis. This gradient was dependent on ankyrinG, an AIS-restricted membrane adaptor protein that recruits NF186. In the absence of neurofascin gradient, basket axons lost directional growth along Purkinje neurons and precisely followed NF186 to ectopic locations. Disruption of NF186-ankyrinG interactions at AIS reduced pinceau synapse formation. These results implicate ankyrin-based localization of L1CAMs in subcellular organization of GABAergic synapses.

Full Text

Duke Authors

Cited Authors

  • Ango, F; di Cristo, G; Higashiyama, H; Bennett, V; Wu, P; Huang, ZJ

Published Date

  • October 15, 2004

Published In

Volume / Issue

  • 119 / 2

Start / End Page

  • 257 - 272

PubMed ID

  • 15479642

International Standard Serial Number (ISSN)

  • 0092-8674

Digital Object Identifier (DOI)

  • 10.1016/j.cell.2004.10.004


  • eng

Conference Location

  • United States