title: Endocytosis of the glutamate receptor subunit GluK3 controls polarized trafficking.
abstract: Kainate receptors (KARs) are widely expressed in the brain and are present at both presynaptic and postsynaptic sites. GluK3-containing KARs are thought to compose presynaptic autoreceptors that facilitate hippocampal mossy fiber synaptic transmission. Here we identify molecular mechanisms that underlie the polarized trafficking of KARs composed of the GluK3b splice variant. Endocytosis followed by degradation is driven by a dileucine motif on the cytoplasmic C-terminal domain of GluK3b in heterologous cells, in cultured hippocampal neurons, and in dentate granule cells from organotypic slice cultures. The internalization of GluK3b is clathrin and dynamin2 dependent. GluK3b is differentially endocytosed in dendrites as compared to the axons. These data suggest that the polarized trafficking of KARs in neurons could be controlled by the regulation of receptor endocytosis.
authors.affiliation: University of Bordeaux, Interdisciplinary Institute for Neuroscience, and CNRS UMR 5297, F-33000 Bordeaux, France.
authors.forename: Deborah
authors.initials: D
authors.lastname: Huyghe
authors.forename: Julien
authors.initials: J
authors.lastname: Veran
authors.forename: Virginie F
authors.initials: VF
authors.lastname: Labrousse
authors.forename: David
authors.initials: D
authors.lastname: Perrais
authors.forename: Christophe
authors.initials: C
authors.lastname: Mulle
authors.forename: Françoise
authors.initials: F
authors.lastname: Coussen
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D019556:COS Cells; D016764:Cell Polarity / Q000235:genetics*; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D004705:Endocytosis / Q000235:genetics*; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009924:Organ Culture Techniques; D021122:Protein Subunits / Q000378:metabolism* / Q000502:physiology; D021381:Protein Transport / Q000235:genetics; D012326:RNA Splicing / Q000235:genetics; D018092:Kainic Acid Receptors / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D000097808:GluK3 Kainate Receptor
chemical_list: D021122:Protein Subunits; D018092:Kainic Acid Receptors; D000097808:GluK3 Kainate Receptor