Cognition, Behavior, and Memory
Author: Santiago Ojea Ramos | email: ojea.santiago@gmail.com
Santiago Ojea Ramos 1°, María del Carment Krawczyk 2°, Candela Medina 2°, Julieta Millan 2°, María Florencia Acutain 3°, María Verónica Baez 3°, Arturo Gabriel Romano 1°, Mariano Martin Boccia 2°, Mariana Feld 1°
1° Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), UBA-CONICET.
2° Laboratorio de Neurofarmacología de Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica UBA.
3° Instituto de Biología Celular y Neurociencias Prof. Dr. E. de Robertis (IBCN, CONICET-UBA).
While ERK1/2 phosphorylation has been extensively studied regarding memory and plasticity, little is known about the role of dimerization in those processes. Here we report preliminary results using native gel electrophoresis to assess the level of ERK2 dimerization generated by glycine-induced chemical long-term potentiation (cLTP) in mature primary cultures of rat cortex neurons, and in mice hippocampus after inhibitory avoidance (IA) memory reactivation. We also evaluated the effect of DEL-22379, a recently developed specific ERK dimerization inhibitor (non affecting phosphorylation), on IA memory reconsolidation and cLTP. We found that cLTP induced ERK2 dimerization in mature cultured neurons, which was inhibited by DEL-22379 addition to the culture media. Additionally, memory reactivation induced a significant decrease of ERK2 dimerization in IA trained mice. Furthermore, intrahippocampal infusion of DEL-22379 after memory reactivation had a surprising bidirectional effect: while it blocked reconsolidation of a strong IA memory, the opposite effect was observed on reconsolidation of a weak IA memory, resulting in its enhancement. This is the first report showing ERK dimerization in neuronal tissues and DEL-22379 effect on plasticity and memory processes. Although more research is needed, these initial findings suggest a relevant role of ERK dimerization in plasticity and memory.