Reduced Calcium Channel Function in Drosophila Disrupts Associative Learning in Larva and Behavior in Adults

The temperature sensitive nature of a mutation in the Cacophony gene, which codes for the alpha subunit in the voltage-gated Ca2+ channel, reduces Ca2+ influx when exposed to non-permissive temperatures. We investigated the subtle nature in the impact for this mutation on whole animal function, in regards to learning and memory, in larvae and adults. The effects in acutely reducing evoked Ca2+ influx in nerve terminals during various behavioural assays greatly decreased the ability of larval Drosophila to learn, as demonstrated in associative learning assays. These assays are based on olfaction and gustation with association to light or dark environments with negative reinforces. Adult flies also showed defects in olfaction and sense of light when the animal is acutely depressed in normal Ca2+ influx within the nervous system. We demonstrated that this particular mutation does not alter cardiac function acutely. Thus, implying that the alpha 1 subunit mutation which retards neuronal function is not relevant for the pace maker and cardiac contractility as indexed by heart rate.