Premium
GLAST / EAAT1 ‐induced Glutamine release via SNAT3 in Bergmann glial cells: evidence of a functional and physical coupling
Author(s) -
MartínezLozada Zila,
Guillem Alain M.,
FloresMéndez Marco,
HernándezKelly Luisa C.,
Vela Carmelita,
Meza Enrique,
Zepeda Rossana C.,
Caba Mario,
Rodríguez Angelina,
Ortega Arturo
Publication year - 2013
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/jnc.12211
Subject(s) - glutamate receptor , glutamine , glutamatergic , glutamine synthetase , glutamate aspartate transporter , biology , biochemistry , transporter , neuroglia , synaptic cleft , metabotropic glutamate receptor 6 , neurotransmitter , glutamic acid , microbiology and biotechnology , amino acid , neuroscience , central nervous system , excitatory amino acid transporter , metabotropic glutamate receptor , receptor , gene
Glutamate, the major excitatory transmitter in the vertebrate brain, is removed from the synaptic cleft by a family of sodium‐dependent glutamate transporters profusely expressed in glial cells. Once internalized, it is metabolized by glutamine synthetase to glutamine and released to the synaptic space through sodium‐dependent neutral amino acid carriers of the N System ( SNAT3 /slc38a3/ SN1 , SNAT5 /slc38a5/ SN2 ). Glutamine is then taken up by neurons completing the so‐called glutamate/glutamine shuttle. Despite of the fact that this coupling was described decades ago, it is only recently that the biochemical framework of this shuttle has begun to be elucidated. Using the established model of cultured cerebellar Bergmann glia cells, we sought to characterize the functional and physical coupling of glutamate uptake and glutamine release. A time‐dependent Na + ‐dependent glutamate/aspartate transporter/ EAAT1 ‐induced System N‐mediated glutamine release could be demonstrated. Furthermore, D‐aspartate, a specific glutamate transporter ligand, was capable of enhancing the co‐immunoprecipitation of Na + ‐dependent glutamate/aspartate transporter and Na + ‐dependent neutral amino acid transporter 3, whereas glutamine tended to reduce this association. Our results suggest that glial cells surrounding glutamatergic synapses may act as sensors of neuron‐derived glutamate through their contribution to the neurotransmitter turnover.