The neuronal and molecular basis of associative olfactory learning in Drosophila larvae


May 13, 2016 - 2:00pm
Northwest 243
About the Speaker
Andi Thum (University of Konstanz)

Memory formation is a highly complex and dynamic process. It consists of different phases, which depend on various neuronal and molecular mechanisms.

In adult Drosophila it was shown that memory formation after aversive Pavlovian conditioning includes - besides other forms - a labile short-term component that consolidates within hours to a longer-lasting memory.

Accordingly, memory formation requires the timely controlled action of different neuronal circuits, neurotransmitters, neuromodulators and molecules that were initially identified by classical forward genetic approaches.

Compared to adult Drosophila, memory formation was only sporadically analyzed at its larval stage. Here we deconstruct the larval mnemonic organization after aversive olfactory conditioning.
We show that after odor-high salt conditioning larvae form an anesthesia resistant memory (lARM). On the molecular level, lARM relies on radish gene function and protein kinase C activity.

In contrast, lARM formation is independent of the cAMP-PKA pathway and de novo protein synthesis. On the neuronal level presynaptic output of mushroom body Kenyon cells and dopamine function is required.

Given the numerical simplicity of the larval nervous system, combined with its upcoming connectome, this work offers a unique prospect for studying memory formation of an exclusively established,
clearly defined specification, at full-brain scope with single-cell, and single-synapse resolution.