The insect chemoreceptor superfamily of the parasitoid jewel wasp Nasonia vitripennis

Abstract

Chemoreception is important for locating food, mates and other resources in many insects, including the parasitoid jewel wasp Nasonia vitripennis. In the insect chemoreceptor superfamily, Nasonia has 58 gustatory receptor (Gr) genes, of which 11 are pseudogenes, leaving 47 apparently intact proteins encoded. No carbon dioxide receptors, two candidate sugar receptors, a DmGr43a orthologue, and several additional Gr lineages were identified, including significant gene subfamily expansions related to the 10 Grs found in the honey bee Apis mellifera. Nasonia has a total of 301 odorant receptor (Or) genes, of which 76 are pseudogenes, leaving 225 apparently intact Ors. Phylogenetic comparison with the 174 honey bee Ors reveals differential gene subfamily expansion in each hymenopteran lineage, along with a few losses from each species. The only simple orthologous relationship is the expected single DmOr83b orthologue. The large number of Nasonia Ors is the result of several major subfamily expansions, including one of 55 genes. Nasonia does not have the elaborate social chemical communication of honey bees, nor the diversity of floral odours honey bees detect, however, Nasonia wasps might need to detect a diversity of odours to find potential mates and hosts or avoid harmful substances in its environment.