A cis-complex of NB-2/contactin-5 with amyloid precursor-like protein 1 is localized on the presynaptic membrane

Neurosci Lett. 2012 Feb 29;510(2):148-53. doi: 10.1016/j.neulet.2012.01.026. Epub 2012 Jan 21.

Abstract

NB-2/contactin-5 plays an important role in synapse formation in the developing auditory system of rodents. In this study, to further elucidate the molecular role of NB-2 in synapse formation, we examined the interaction between NB-2 and amyloid precursor-like protein 1 (APLP1), as well as their possible co-localization at the synapse. Pull-down assays and cell surface binding assays demonstrated that NB-2 interacts with APLP1. Furthermore, the protein expression profile of APLP1 in western blots was similar to that of NB-2, and localization of APLP1 mRNA partially overlapped that of NB-2 mRNA. In cultured hippocampal neurons, immunofluorescence signals for both NB-2 and APLP1 overlapped with synapsin, a presynaptic marker. Biochemical analysis showed that both NB-2 and APLP1 were enriched in the presynaptic fraction. These results indicate that NB-2 forms a cis-complex with APLP1 on the presynaptic membrane.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyloid beta-Protein Precursor / metabolism*
  • Animals
  • Blotting, Western
  • Brain / growth & development
  • Brain / metabolism*
  • Cell Adhesion Molecules, Neuronal / metabolism*
  • Cells, Cultured
  • Fluorescent Antibody Technique
  • Hippocampus / metabolism
  • In Situ Hybridization
  • Mice
  • Mice, Inbred C57BL
  • Neurons / metabolism
  • Presynaptic Terminals / metabolism
  • Recombinant Fusion Proteins / metabolism
  • Synaptic Membranes / metabolism*

Substances

  • Amyloid beta-Protein Precursor
  • Aplp1 protein, mouse
  • Cell Adhesion Molecules, Neuronal
  • NB-2 protein, mouse
  • Recombinant Fusion Proteins