Epigenetic mechanisms in object recognition memory: histone acetylation as a molecular feature of strong memories

NOEL FEDERMAN, VERÓNICA DE LA FUENTE, GISELA PATRICIA ZALCMAN Y ARTURO ROMANO

Córdoba

Congreso; SAN 2011; 2011

Sociedad Argentina de Neurociencias (SAN)

Long-term memory (LTM) consolidation requires mRNA and de novo protein synthesis. Transcription is controlled by transcription factors, their cofactors and repressors. Some cofactors can regulate gene expression by chemically modifying histones. Acetylation is the most studied histone modification related to gene expression regulation. This process is regulated by lysine acetylases (HATs) and deacetylases (HDACs). Here, we found evidence supporting that histone acetylation is involved in consolidation of novel object recognition memory in mice. We showed that hippocampal HDACs inhibition enhanced recognition memory. We found that standard and strong trainings produced LTM at 24 hours testing. However, strong trained mice showed significant higher levels of object discrimination than standard trained mice when we tested one week after training. Accordingly, only a strong training induced a general increase of hippocampal H3 acetylation 1 h after training. In order to evaluate the level of H3 acetylation in a particular gene, we are currently performing ChIP assay on the promoter regions of zif268 and BDNF gene. Based on our results, we hypothesize that histone acetylation is a key mechanism in LTM persistence, functioning as a molecular feature of stronger memories.