Rapid degradation of odours after interaction with olfactory receptors is a critical step of the signal reception process. However, the implied mechanisms are still largely unknown in vertebrates as well as in insects. Involvement of odourant-degrading enzymes in odourant degradation within the antennae has been shown in some insect species and, in particular, esterases could play a key role in degradation of sex pheromones from Lepidoptera. Using a PCR-based strategy, we isolated cDNAs encoding two new esterases from two moths which used acetates as pheromone compounds: the Egyptian armyworm Spodoptera littoralis and the Mediterranean corn borer Sesamia nonagrioides. In antennae, both transcripts were clearly restricted to olfactory sensilla, suggesting their involvement in the degradation of odourant acetate components.

This work was supported by Université Paris VI, INRA, an Ile-de-France region graduate fellowship to C. Merlin, and a PICASSO API fellowship. We also thank CICYT (Project AGL2003-06599-C02-01), Generalitat de Catalunya (ACI, 2002) and MEC (HF2004-0272) for financial support.

9 pages, 5 figures.-- PMID: 17257210 [PubMed].

Peer reviewed