The Effects of SNMP-2 Gene Expression on Mating Discrimination in Male Drosophila Melanogaster

In order to distinguish between relevant and extraneous stimuli, insects have adapted specialized processes to perceive cues that are beneficial for survival and proliferation. Volatile molecules in the environment can stimulate olfactory receptors (ORs) and gustatory receptors (GRs) in chemosensory organs called sensilla. Specialized proteins located within these sensilla guide and assist chemosensory molecules to the receptors, which then trigger a transduction pathway that elicits behavioral responses. Sensory Neuron Membrane Proteins (SNMPs) are transmembrane proteins found on both gustatory and olfactory sensory organs in insects. There are two forms of these proteins, SNMP-1 and SNMP-2. InDrosophila melanogaster, the function of the SNMPs is currently unknown, but it is thought to contribute to proper recognition of pheromones secreted by maleDrosophila. To determine the role of SNMP-2 inDrosophila, we reduced the gene expression of SNMP-2 by targeting the gene with RNA-mediated gene interface (RNAi). We then recorded courtship displays of male-male and male-female interactions and found that reduction of SNMP-2 increased the frequency at which males courted other males, but did not affect that of which males courted females. Results were confirmed by quantitative real time PCR.