Role of ADF/cofilin as a key regulator of actin cytoskeleton dynamics in different phases of fear memory in mice

MEDINA, CANDELA; DE LA FUENTE, VERÓNICA; ROMANO, ARTURO

Buenos Aires

Congreso; II Congreso de la Federación de Sociedades Neurocientíficas de Latinoamérica y el Caribe; 2016

Federación de Sociedades Neurocientíficas de Latinoamérica y el Caribe

Given an associative learning, memory can become stablethrough a process termed consolidation. If afterwardsmemory retrieval is induced by non-reinforced re-exposureto the conditioned stimulus and depending of thecharacteristics of that re-exposure, the original memorytrace can undergo either reconsolidation or extinction.These processes entail alterations in synaptic efficacy,which in turn depends on the regulation of dendriticspines? morphology. Since dendritic spines are main sitesof information processing and storage in the brain, actindynamics in these neural structures has became a centraltopic in the study of memory. Our main goal is to analyzemolecular mechanisms underlying the regulation of actindynamics, focusing on the depolymerizing factor ADF/cofilin and its role on different phases of memory using acontextual fear conditioning paradigm in mice. For thatpurpose we first increased this factor?s activity specificallyin dorsal hippocampus by inhibiting its key regulator, LIMkinase. Preliminary results indicate that increasing thedepolimerization rate produces a memory impairmentwhen done so before training session or immediately afterre-exposure to the training context. Importantly, druginjected non-reexposed animals do not show memoryimpairment, revealing the specificity of the effect onmemory reconsolidation. These results support a key roleof LIM kinase in the processes of memory acquisition/consolidation and reconsolidation