title: The role of the PDZ protein GIPC in regulating NMDA receptor trafficking.
abstract: The NMDA receptor is an important component of excitatory synapses in the CNS. In addition to its synaptic localization, the NMDA receptor is also present at extrasynaptic sites where it may have functions distinct from those at the synapse. Little is known about how the number, composition, and localization of extrasynaptic receptors are regulated. We identified a novel NMDA receptor-interacting protein, GIPC (GAIP-interacting protein, C terminus), that associates with surface as well as internalized NMDA receptors when expressed in heterologous cells. In neurons, GIPC colocalizes with a population of NMDA receptors on the cell surface, and changes in GIPC expression alter the number of surface receptors. GIPC is mainly excluded from the synapse, and changes in GIPC expression do not change the total number of synaptic receptors. Our results suggest that GIPC may be preferentially associated with extrasynaptic NMDA receptors and may play a role in the organization and trafficking of this population of receptors.
authors.affiliation: Laboratory of Neurochemistry, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Zhaohong
authors.initials: Z
authors.lastname: Yi
authors.forename: Ronald S
authors.initials: RS
authors.lastname: Petralia
authors.forename: Zhanyan
authors.initials: Z
authors.lastname: Fu
authors.forename: Catherine Croft
authors.initials: CC
authors.lastname: Swanwick
authors.forename: Ya-Xian
authors.initials: YX
authors.lastname: Wang
authors.forename: Kate
authors.initials: K
authors.lastname: Prybylowski
authors.forename: Nathalie
authors.initials: N
authors.lastname: Sans
authors.forename: Stefano
authors.initials: S
authors.lastname: Vicini
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Wenthold
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000502:physiology*; D002522:Chlorocebus aethiops; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D009479:Neuropeptides / Q000502:physiology*; D021381:Protein Transport / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C492008:Gipc1 protein, rat; D009479:Neuropeptides; D016194:Receptors, N-Methyl-D-Aspartate