The role of Arc gene in memory

Brain memory storage and information processing occurs through changes in synaptic connections between neurons or synaptic plasticity. In experimental models of synaptic plasticity such as LTP, stabilization of these changes requires de novo protein synthesis. Immediately after stimulations that induce LTP or behavioral experiments which contribute to Long Term Memory (LTM) formation, Immediate-Early Genes are induced in hippocampal neurons; among neuronal activity dependent IEGs, Arc is of particular importance. Arc is robustly induced by plasticity-producing stimulation and is specifically targeted to stimulated synaptic areas. It also plays a critical role in the maintenance of long term potentiation and in memory consolidation processes. Inhibition of Arc protein expression in the rat hippocampus, through ODNs infusion, impairs maintenance of LTP and consolidation of LTM. Thus, Arc appears to play a fundamental role in stabilization of activity-dependent hippocampal plasticity. In this paper, the role of Arc in memory formation is discussed.