Impact of mutation in odor receptor (Or42a) on the circadian locomotor activity rhythm of Drosophila melanogaster

In animals olfaction is mediated by the interaction of volatile ligands with a set of specialized membrane proteins known as odorant receptors (Ors). An intriguing question in the biology of the sensory system concerns the equivalency of its primary sensory neurons in driving behavioral outputs, particularly navigational ability towards food and temporal locomotor activity. It has been established that olfactory and gustatory receptors of the fruitfly Drosophila melanogaster are regulated by the circadian clock system. In this study, an attempt has been made to discover the impact of a mutation in a specific olfactory receptor (Or42a –essentially responsive to the odorant 4-hexen-3-one) on the circadian locomotor activity rhythms. The mutant alleles of Or42a (stock no. 18758 from the Drosophila Stock Center (Bloomington, IN)) were used in this study. Mutant lines were backcrossed to a  w¹¹¹⁸ line for 10 generations. Males and females of both mutant and wild type strains were analyzed for their locomotor activity rhythms in a Trikinetics Drosophila Activity Monitor. This analysis would provide a foundation for elucidating how odor receptors impact behavioral outputs.