Conditioning deficits of CaM-kinase transgenic Drosophila melanogaster in a new excitatory courtship assay.

摘要

Courtship suppression is an associative conditioning procedure in Drosophila melanogaster that is ethologically based and capable of being tested on individual flies. We have expanded the range of the courtship conditioning by developing an excitatory procedure in which male flies learn to associate a novel odor with the courtship stimulating cues of virgin females. Wild-type males normally court other mature males very little, but following training, the odor alone is able to elicit increased levels of courtship towards an object male. Flies expressing an inhibitor of calcium/calmodulin-dependent protein kinase II (CaMKII) were previously shown to have no retention one hour after training in the courtship suppression task, as manifested in their persistent courting of a virgin female. A possible trivial explanation for this response is that the CaMKII-inhibited fly strains (ala1 and ala2) were merely hyperactive courters. The poor performance of these mutants in the new excitatory conditioning procedure confirms that their conditioning deficit results from a disruption of an associative mechanism per se.