Involvement of δCaMKII in persistent forms of memory

GISELA ZALCMAN; NOEL FEDERMAN; NOEL FEDERMAN; ARTURO ROMANO

Congreso; XXX SAN ANNUAL MEETING; 2015

Calcium/calmodulin-dependent protein kinase II (CaMKII) is an abundant synapticsignaling molecule that is essential for both memory formation and synaptic potentiation. In mammals, CaMKII exists in multiple isoforms that are the product of four closely related genes: α, β, γ, and δ. Little information is known about the role of δCaMKII in memory processes. In a previous study, we showed that in the mouse hippocampus camk2d gene was specifically expressed during the formation of persistent forms of novel object recognition (NOR) memory and that its gene promoter was acetylated during this process on a NF-кB dependent manner. Here, we will present new results in which we show that δCaMKII mRNA expression is increased at different time-points during NOR memory maintenance returning to control levels 20 days after training, once memory retention decays. The increment in its mRNA expression is accompanied by changes in nucleosome positioning on its promoter. Moreover, δCaMKII knock-down after training impairs object recognition memory when assessed one week later. Altogether, our results support a key role for δCaMKII in persistent forms of memory and suggest that δCaMKII may have a sustained expression throughout the ?lifetime? of this kind of memory. Furthermore, this is the first work that provides insight information about nucleosome remodeling during memory formation and maintenance.