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Exposure to novel environments (NE) induces structural and functional changes in multiple brain areas, including the hippocampus, driven in part by changes in gene expression. However, the cell-type-specific transcriptional and chromatin responses to NE remain poorly understood. We employed single-nucleus multiomics and bulk RNA-seq of the hippocampal DG, CA3, and CA1 regions of male mice to profile gene expression and chromatin accessibility following NE exposure. We observed region-specific responses in excitatory neurons and diverse transcriptional changes in inhibitory and non-neuronal cells. NE-regulated genes were enriched for secreted factors, and their cell-type-specific receptor expression highlighted candidate signaling pathways involved in learning and memory. We identified thousands of cell-type-specific chromatin accessibility changes, with coordinated expression and accessibility patterns implicating FOS/AP-1 as a key regulator. These data provide a rich resource of chromatin accessibility and gene expression profiles across hippocampal cell types in response to NE, a physiological stimulus affecting learning and memory.