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Hippocampal circuit dysfunction in the Tc1 mouse model of Down syndrome
journal contributionposted on 2020-09-22, 13:58 authored by Jonathan Witton, Ragunathan Padmashri, Larissa E Zinyuk, Victor I Popov, Igor Kraev, Samantha J Line, Thomas P Jensen, Angelo Tedoldi, Damian M Cummings, Victor LJ Tybulewicz, Elizabeth MC Fisher, David M Bannerman, Andrew D Randall, Jonathan T Brown, Frances A Edwards, Dmitri A Rusakov, Michael G Stewart, Matt W Jones
Hippocampal pathology is likely to contribute to cognitive disability in Down syndrome, yet the neural network basis of this pathology and its contributions to different facets of cognitive impairment remain unclear. Here we report dysfunctional connectivity between dentate gyrus and CA3 networks in the transchromosomic Tc1 mouse model of Down syndrome, demonstrating that ultrastructural abnormalities and impaired short-term plasticity at dentate gyrus-CA3 excitatory synapses culminate in impaired coding of new spatial information in CA3 and CA1 and disrupted behavior in vivo. These results highlight the vulnerability of dentate gyrus-CA3 networks to aberrant human chromosome 21 gene expression and delineate hippocampal circuit abnormalities likely to contribute to distinct cognitive phenotypes in Down syndrome.
AnimalsCA3 Region, HippocampalChromosomes, Human, Pair 21Dentate GyrusDisease Models, AnimalDown SyndromeHumansMaleMaze LearningMiceMice, 129 StrainMice, Inbred C57BLNerve NetOrgan Culture TechniquesTrisomyTybulewicz U117527252Neurology & Neurosurgery1109 Neurosciences1702 Cognitive Sciences1701 Psychology