Modeling the human cognitive impairment candidate genes in Drosophila Melanogaster: report on a systematic study on olfactory classical conditioning behavior test

Background and Aim : Basic biological, physiological, and neurological properties are conserved between human and Drosophila Melanogaster. About 75% of human disease-causing genes have a functional homolog in Drosophila. The mechanism of memory formation and learning process are also similar between human and fruit fly. Drosophila Melanogaster can recognize and remember odors to make a response, based on neurotic plasticity. Studies of olfactory learning in Drosophila have provided key insights into the brain mechanisms underlying learning and memory.Methods : One type of olfactory learning, olfactory classical conditioning, consists of learning the contingency between an odor with an aversive or appetitive stimulus. In the frame of a series of experiments to investigate the role of novel intellectual disability (ID) candidate genes in cognitive behavior, we used Pavlovian conditioning in a T-Maze apparatus. The expression of orthologues of candidate genes were decreased in Drosophila neurons by UAS-GAL4 knock-down system, with the help of a pan neuronal GAL4 (elav).Results : Learning and short term memory following a conditional stimulus were tested. Our primary results showed that knock down of the orthologue of YIF1B (Yip1 interacting factor homolog B) gene in neurons of Drosophila Melanogaster is lethal in late pupal stage, and impaired the olfactory behavior and thus short term memory formationConclusion : Further investigations into the role of other cognitive impairment candidate genes including RABAC1(prenylated Rab acceptor protein 1), and RHBDF1(rhomboid 5 homolog 1) are ongoing.

Keywords:

Drosophila melanogaster , Functional Study , Olfactory learning , Pavlovian conditioning