Impaired spatial coding of the hippocampus in a dentate gyrus hypoplasia mouse model

• DOI: 10.1073/pnas.2416214122
• Publication Date: 2025-01-30T19:12:43Z
• Authors: Xiaojing Chen; Ning Cheng; Cheng Wang; James J. Knierim
• Keywords: Entorhinal cortex; Granule cell; Place cell

The hippocampal dentate gyrus (DG) is thought to orthogonalize inputs from the entorhinal cortex (pattern separation) and relay this information CA3 region. In turn, attractor dynamics in perform a pattern completion or error correction operation before sending its output CA1. mouse model of congenital hypoplasia DG, deficiency Wntless (Wls) gene, specifically cells expressing Gfap-Cre , which targets neuronal progenitors, led an almost total absence granule modestly impaired performance spatial tasks. Here, we investigated physiological consequences cell loss these mice by conducting vivo calcium imaging CA1 principal during behavior. selectivity was preserved without DG. On linear track, place fields mutant were more likely be near track terminals encode distance start point each running direction. open box, exhibited reductions percentage cells, information, field stability. reduction stability across repeated exposures same environment resulted differential representations two different contexts compared wild-type mice. These results suggest that DG helps stabilize representations, especially 2-D environments, lack similar environments may play key role deficits animals with dysfunction discriminating environments.