Session: 1


Malena Cortasa

Laboratorio de Neurociencias del Tiempo/ iB3 Instituto de Biociencias, Biotecnología y Biología traslacional/ Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires

The neurobiological basis of time estimation has not been clearly established yet. One hypothesis proposes that it encloses cognitive processes such as attention, learning, working memory, and decision-making. Considering that, time estimation could be a type of short-term memory in which the sole stimulus of time itself is enough to launch the behaviour. In an attempt to understand how the brain processes and utilizes temporal information in the second to minute range, we developed an interval timing experimental setup in Drosophila melanogaster. The core of our experiments is the motivation to drink a sucrose drop that is available for 10 seconds at a fixed interval of 60 seconds. We analyse the animal proboscis extension response (PER) over time. Results showed that training increases the time until PER, anticipating the occurrence of the drop. We operationally define time-referenced memory as a statistically significant increase in PER at the testing interval compared to PER average in the first three intervals. Here we investigate if genes already known to be involved in short-term memory mechanisms are also engaged in time estimation, beginning by sarah. Sarah is a serine/threonine phosphatase that regulates calcineurin activity. We will downregulate sarah both chronically and acutely over mushroom bodies by expressing its RNAi, to study learning and memory. If we confirm sarah’s involvement in time-referenced memory we will continue with the calcineurin pathway.