Send to

Choose Destination
See comment in PubMed Commons below
J Cell Biol. 2002 Jun 24;157(7):1197-209. Epub 2002 Jun 17.

Modulation of receptor cycling by neuron-enriched endosomal protein of 21 kD.

Author information

Faculté des Sciences de la Vie, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.


Although correct cycling of neuronal membrane proteins is essential for neurite outgrowth and synaptic plasticity, neuron-specific proteins of the implicated endosomes have not been characterized. Here we show that a previously cloned, developmentally regulated, neuronal protein of unknown function binds to syntaxin 13. We propose to name this protein neuron-enriched endosomal protein of 21 kD (NEEP21), because it is colocalized with transferrin receptors, internalized transferrin (Tf), and Rab4. In PC12 cells, NEEP21 overexpression accelerates Tf internalization and recycling, whereas its down-regulation strongly delays Tf recycling. In primary neurons, NEEP21 is localized to the somatodendritic compartment, and, upon N-methyl-d-aspartate (NMDA) stimulation, the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor subunit GluR2 is internalized into NEEP21-positive endosomes. NEEP21 down-regulation retards recycling of GluR1 to the cell surface after NMDA stimulation of hippocampal neurons. In summary, NEEP21 is a neuronal protein that is localized to the early endosomal pathway and is necessary for correct receptor recycling in neurons.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons


    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center