Histone acetylation is recruited in consolidation as a molecular feature of stronger memories.
Gene expression is a key process for memory consolidation. Recently, the participation of epigenetic mechanisms like histone acetylation was evidenced in long-term memories. However, until now the training strength required and the persistence of the chromatin acetylation recruited are not well characterized. Here we studied whether histone acetylation is involved in consolidation in invertebrates, whether it depends on the training strength, and whether it is a permanent or transient mechanism. We used a well-characterized memory model in invertebrates, the context-signal memory in crabs. Our results show no changes in histone 3 (H3) acetylation during consolidation of a standard training protocol. However, strong training induced a significant increase in H3 acetylation 1-h post-training, returning to basal levels afterward. Accordingly, the administration of histone deacetylase inhibitors sodium butyrate (NaB) and trichostatin A allowed a weak training to induce long-term memory. NaB enhanced memory in two phases during consolidation. These findings support that H3 acetylation (1) is involved in consolidation, (2) occurs only after strong training, (3) is a transient process, and (4) memory is enhanced in two phases. The coincidence of these phases with other mechanisms of gene expression is discussed.
Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IFIByNE (UBA CONICET), Ciudad Universitaria,1428EHA Buenos Aires, Argentina.
Noel
N
Federman
Maria Sol
MS
Fustiñana
Arturo
A
Romano
D000107:Acetylation / Q000187:drug effects; D000818:Animals; D003386:Brachyura; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006657:Histones / Q000378:metabolism*; D006877:Hydroxamic Acids / Q000494:pharmacology; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*
D056572:Histone Deacetylase Inhibitors; D006657:Histones; D006877:Hydroxamic Acids; C012589:trichostatin A