TY - JOUR
T1 - Corticostriatal dysfunction and social interaction deficits in mice lacking the cystine/glutamate antiporter
AU - Bentea, Eduard
AU - Villers, Agnès
AU - Moore, Cynthia
AU - Funk, Adam J
AU - O'Donovan, Sinead M
AU - Verbruggen, Lise
AU - Lara, Olaya
AU - Janssen, Pauline
AU - De Pauw, Laura
AU - Declerck, Noemi B
AU - DePasquale, Erica A K
AU - Churchill, Madeline J
AU - Sato, Hideyo
AU - Hermans, Emmanuel
AU - Arckens, Lutgarde
AU - Meshul, Charles K
AU - Ris, Laurence
AU - McCullumsmith, Robert E
AU - Massie, Ann
N1 - © 2020. The Author(s).
PY - 2021/9
Y1 - 2021/9
N2 - The astrocytic cystine/glutamate antiporter system xc- represents an important source of extracellular glutamate in the central nervous system, with potential impact on excitatory neurotransmission. Yet, its function and importance in brain physiology remain incompletely understood. Employing slice electrophysiology and mice with a genetic deletion of the specific subunit of system xc-, xCT (xCT-/- mice), we uncovered decreased neurotransmission at corticostriatal synapses. This effect was partly mitigated by replenishing extracellular glutamate levels, indicating a defect linked with decreased extracellular glutamate availability. We observed no changes in the morphology of striatal medium spiny neurons, the density of dendritic spines, or the density or ultrastructure of corticostriatal synapses, indicating that the observed functional defects are not due to morphological or structural abnormalities. By combining electron microscopy with glutamate immunogold labeling, we identified decreased intracellular glutamate density in presynaptic terminals, presynaptic mitochondria, and in dendritic spines of xCT-/- mice. A proteomic and kinomic screen of the striatum of xCT-/- mice revealed decreased expression of presynaptic proteins and abnormal kinase network signaling, that may contribute to the observed changes in postsynaptic responses. Finally, these corticostriatal deregulations resulted in a behavioral phenotype suggestive of autism spectrum disorder in the xCT-/- mice; in tests sensitive to corticostriatal functioning we recorded increased repetitive digging behavior and decreased sociability. To conclude, our findings show that system xc- plays a previously unrecognized role in regulating corticostriatal neurotransmission and influences social preference and repetitive behavior.
AB - The astrocytic cystine/glutamate antiporter system xc- represents an important source of extracellular glutamate in the central nervous system, with potential impact on excitatory neurotransmission. Yet, its function and importance in brain physiology remain incompletely understood. Employing slice electrophysiology and mice with a genetic deletion of the specific subunit of system xc-, xCT (xCT-/- mice), we uncovered decreased neurotransmission at corticostriatal synapses. This effect was partly mitigated by replenishing extracellular glutamate levels, indicating a defect linked with decreased extracellular glutamate availability. We observed no changes in the morphology of striatal medium spiny neurons, the density of dendritic spines, or the density or ultrastructure of corticostriatal synapses, indicating that the observed functional defects are not due to morphological or structural abnormalities. By combining electron microscopy with glutamate immunogold labeling, we identified decreased intracellular glutamate density in presynaptic terminals, presynaptic mitochondria, and in dendritic spines of xCT-/- mice. A proteomic and kinomic screen of the striatum of xCT-/- mice revealed decreased expression of presynaptic proteins and abnormal kinase network signaling, that may contribute to the observed changes in postsynaptic responses. Finally, these corticostriatal deregulations resulted in a behavioral phenotype suggestive of autism spectrum disorder in the xCT-/- mice; in tests sensitive to corticostriatal functioning we recorded increased repetitive digging behavior and decreased sociability. To conclude, our findings show that system xc- plays a previously unrecognized role in regulating corticostriatal neurotransmission and influences social preference and repetitive behavior.
KW - Animals
KW - Antiporters
KW - Autism Spectrum Disorder/genetics
KW - Cystine
KW - Glutamic Acid
KW - Mice
KW - Proteomics
KW - Social Interaction
U2 - 10.1038/s41380-020-0751-3
DO - 10.1038/s41380-020-0751-3
M3 - Article
C2 - 32366950
SN - 1359-4184
VL - 26
SP - 4754
EP - 4769
JO - Molecular Psychiatry
JF - Molecular Psychiatry
IS - 9
ER -