Genome-wide maps of chromatin changes uppon contextual fear conditioning in mice (meDIP-seq)

The ability to form memories is a prerequisite for an organism’s behavioural adaptation to environmental changes. At the molecular level, the acquisition and maintenance of memory requires changes in chromatin modifications. In an effort to unravel the epigenetic network underlying both short- and long-term memory, we examined chromatin modification changes in two distinct mouse brain regions, two cell-types, and three time-points before and after contextual learning. Here we show that histone modifications predominantly change during memory acquisition and correlate surprisingly little with changes in gene expression. While long-lasting changes are almost exclusive to neurons, learning-related histone modification and DNA methylation changes occur also in non-neuronal cell types, suggesting a functional role for non-neuronal cells in epigenetic learning. Finally, our data provides evidence for a molecular framework of memory acquisition and maintenance, wherein DNA methylation could alter the expression and splicing of genes involved in functional plasticity and synaptic wiring. Overall design: We examined chromatin modification changes in two distinct mouse brain regions (CA1 and ACC), two cell-types (neurons, non-neurons), and three time-points before and after contextual learning (naive, 1h, 4w).