Study of ADF/cofilin as a regulator of actin cytoskeleton dynamics in fear memory labilization and reconsolidation

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

Montevideo

Congreso; XII Congreso de la Sociedad Internacional de Neuroetología; 2016

Sociedad Internacional de Neuroetología

Consolidation is the process by which new information is encoded in neural circuits. However, once a memory is consolidated it does not remain stable forever. In particular, it can change over experience. When a reminder of the learning event is presented to an animal that has learnt something new, the memory and thus the neural circuits that encode that memory, becomes labile and need a process of reconsolidation to be re-stabilized. Several studies support the fact that consolidation entails neuronal morphologic changes, like modifications of spine density and morphology. Nevertheless, no data is available regarding changes in neuronal morphology related to labilization and reconsolidation of memory. Besides, actin cytoskeleton plays a key role in cellular morphogenesis and is, therefore, important in the processes that underlies modification of spine morphology. Actin dynamics between its monomeric form and its filamentous polymer is finely regulated by many factors, including ADF/cofilin, a protein with depolymerizing activity. ADF/cofilin has recently emerged as a central determinant for many memory processes, including acquisition and extinction. Yet, its role on regulating actin cytoskeleton during memory labilization and reconsolidation is still unknown. In our work, we approached this issue by first studying actin dynamics after a reminder that elicits these processes, using a fear conditioning paradigm in mice.