Dual Function of NRP1 in Axon Guidance and Subcellular Target Recognition in Cerebellum

Neuron. 2016 Sep 21;91(6):1276-1291. doi: 10.1016/j.neuron.2016.08.015. Epub 2016 Sep 8.

Abstract

Subcellular target recognition in the CNS is the culmination of a multiple-step program including axon guidance, target recognition, and synaptogenesis. In cerebellum, basket cells (BCs) innervate the soma and axon initial segment (AIS) of Purkinje cells (PCs) to form the pinceau synapse, but the underlying mechanisms remain incompletely understood. Here, we demonstrate that neuropilin-1 (NRP1), a Semaphorin receptor expressed in BCs, controls both axonal guidance and subcellular target recognition. We show that loss of Semaphorin 3A function or specific deletion of NRP1 in BCs alters the stereotyped organization of BC axon and impairs pinceau synapse formation. Further, we identified NRP1 as a trans-synaptic binding partner of the cell adhesion molecule neurofascin-186 (NF186) expressed in the PC AIS during pinceau synapse formation. These findings identify a dual function of NRP1 in both axon guidance and subcellular target recognition in the construction of GABAergic circuitry.

MeSH terms

  • Animals
  • Axon Guidance / physiology*
  • CHO Cells
  • Cell Adhesion Molecules / metabolism
  • Cerebellum / cytology*
  • Cerebellum / growth & development*
  • Coculture Techniques
  • Cricetulus
  • GABAergic Neurons / physiology*
  • Humans
  • Nerve Growth Factors / metabolism
  • Neurogenesis / physiology
  • Neuropilin-1 / physiology*
  • Purkinje Cells / physiology
  • Semaphorin-3A / physiology
  • Synapses / physiology

Substances

  • Cell Adhesion Molecules
  • Nerve Growth Factors
  • Nfasc protein, mouse
  • Semaphorin-3A
  • Neuropilin-1