mRNA translation in astrocytes controls hippocampal long-term synaptic plasticity and memory.

Activation of neuronal protein synthesis upon learning is critical for the formation of long-term memory. Here, we report that learning in the contextual fear conditioning paradigm engenders a decrease in eIF2a (eukaryotic translation initiation factor 2) phosphorylation in astrocytes in the hippocampal CA1 region, which promotes protein synthesis. Genetic reduction of eIF2a phosphorylation in hippocampal astrocytes enhanced contextual and spatial memory and lowered the threshold for the induction of long-lasting plasticity by modulating synaptic transmission. Thus, learning-induced dephosphorylation of eIF2a in astrocytes bolsters hippocampal synaptic plasticity and consolidation of long-term memories. [ABSTRACT FROM AUTHOR]