A novel sorting motif in the glutamate transporter excitatory amino acid transporter 3 directs its targeting in Madin-Darby canine kidney cells and hippocampal neurons.

@article{citeulike:766723, abstract = {The glutamate transporter excitatory amino acid transporter 3 (EAAT3) is polarized to the apical surface in epithelial cells and localized to the dendritic compartment in hippocampal neurons, where it is clustered adjacent to postsynaptic sites. In this study, we analyzed the sequences in EAAT3 that are responsible for its polarized localization in Madin-Darby canine kidney (MDCK) cells and neurons. Confocal microscopy and cell surface biotinylation assays demonstrated that deletion of the EAAT3 C terminus or replacement of the C terminus of EAAT3 with the analogous region in EAAT1 eliminated apical localization in MDCK cells. The C terminus of EAAT3 was sufficient to redirect the basolateral-preferring EAAT1 and the nonpolarized EAAT2 to the apical surface. Using alanine substitution mutants, we identified a short peptide motif in the cytoplasmic C-terminal region of EAAT3 that directs its apical localization in MDCK cells. Mutation of this sequence also impairs dendritic targeting of EAAT3 in hippocampal neurons but does not interfere with the clustering of EAAT3 on dendritic spines and filopodia. These data provide the first evidence that an identical cytoplasmic motif can direct apical targeting in epithelia and somatodendritic targeting in neurons. Moreover, our results demonstrate that the two fundamental features of the localization of EAAT3 in neurons, its restriction to the somatodendritic domain and its clustering near postsynaptic sites, are mediated by distinct molecular mechanisms.}, address = {Howard Hughes Medical Institute, Oregon Health and Science University, Portland, Oregon 97239, USA.}, author = {Cheng, C. and Glover, G. and Banker, G. and Amara, S. G. }, citeulike-article-id = {766723}, issn = {1529-2401}, journal = {J Neurosci}, keywords = {dendrites, motif, somatodendritic, targeting}, month = {December}, number = {24}, pages = {10643--10652}, posted-at = {2006-07-20 16:16:47}, priority = {0}, title = {A novel sorting motif in the glutamate transporter excitatory amino acid transporter 3 directs its targeting in Madin-Darby canine kidney cells and hippocampal neurons.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/12486157}, volume = {22}, year = {2002} }

TY - JOUR ID - citeulike:766723 L3 - citeulike-article-id:766723 TI - A novel sorting motif in the glutamate transporter excitatory amino acid transporter 3 directs its targeting in Madin-Darby canine kidney cells and hippocampal neurons. JF - J Neurosci VL - 22 IS - 24 SP - 10643 EP - 10652 AD - Howard Hughes Medical Institute, Oregon Health and Science University, Portland, Oregon 97239, USA. SN - 1529-2401 N2 - The glutamate transporter excitatory amino acid transporter 3 (EAAT3) is polarized to the apical surface in epithelial cells and localized to the dendritic compartment in hippocampal neurons, where it is clustered adjacent to postsynaptic sites. In this study, we analyzed the sequences in EAAT3 that are responsible for its polarized localization in Madin-Darby canine kidney (MDCK) cells and neurons. Confocal microscopy and cell surface biotinylation assays demonstrated that deletion of the EAAT3 C terminus or replacement of the C terminus of EAAT3 with the analogous region in EAAT1 eliminated apical localization in MDCK cells. The C terminus of EAAT3 was sufficient to redirect the basolateral-preferring EAAT1 and the nonpolarized EAAT2 to the apical surface. Using alanine substitution mutants, we identified a short peptide motif in the cytoplasmic C-terminal region of EAAT3 that directs its apical localization in MDCK cells. Mutation of this sequence also impairs dendritic targeting of EAAT3 in hippocampal neurons but does not interfere with the clustering of EAAT3 on dendritic spines and filopodia. These data provide the first evidence that an identical cytoplasmic motif can direct apical targeting in epithelia and somatodendritic targeting in neurons. Moreover, our results demonstrate that the two fundamental features of the localization of EAAT3 in neurons, its restriction to the somatodendritic domain and its clustering near postsynaptic sites, are mediated by distinct molecular mechanisms. KW - dendrites KW - motif KW - somatodendritic KW - targeting AU - Cheng, C AU - Glover, G AU - Banker, G AU - Amara, SG PY - 2002/12/15/ UR - http://view.ncbi.nlm.nih.gov/pubmed/12486157 ER -