The molecular characterization of post-receptor actors involved in insect olfactory transduction has yet to be understood. We have investigated the presence of a Transient Receptor Potential (TRP) channel in the peripheral olfactory system of the moth Spodoptera littoralis. A cDNA encoding a Lepidopteran TRP channel (TRPγ) was identified by analysis of a male-antennal EST database and subsequently cloned by RACE PCR. In adult males, the TRPγ transcript was detected in antennae, at the base of olfactory sensilla. Moreover, TRPγ was observed in antennae in both pupal and adult stages. This work is the first step in understanding the involvement of TRPγ in signalling pathways involved in the development and function of the insect olfactory system.