Epigenetic Mechanisms: Critical Contributors to Long-Term Memory Formation

Department of Neurobiology, Evelyn F McKnight Brain Institute, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
The Neuroscientist (Impact Factor: 7.62). 12/2011; 17(6):616-32. DOI: 10.1177/1073858411386967
Source: PubMed

ABSTRACT Recent advances in chromatin biology have identified a role for epigenetic mechanisms in the regulation of neuronal gene expression changes, a necessary process for proper synaptic plasticity and memory formation. Experimental evidence for dynamic chromatin remodeling influencing gene transcription in postmitotic neurons grew from initial reports describing posttranslational modifications of histones, including phosphorylation and acetylation occurring in various brain regions during memory consolidation. An accumulation of recent studies, however, has also highlighted the importance of other epigenetic modifications, such as DNA methylation and histone methylation, as playing a role in memory formation. This present review examines learning-induced gene transcription by chromatin remodeling underlying long-lasting changes in neurons, with direct implications for the study of epigenetic mechanisms in long-term memory formation and behavior. Furthermore, the study of epigenetic gene regulation, in conjunction with transcription factor activation, can provide complementary lines of evidence to further understanding transcriptional mechanisms subserving memory storage.

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