The chemoreceptor superfamily in the honey bee, Apis mellifera : Expansion of the odorant, but not gustatory, receptor family

The honey bee genome sequence reveals a remarkable expansion of the insect odorant receptor (Or) family relative to the repertoires of the flies Drosophila melanogaster and Anopheles gambiae, which have 62 and 79 Ors respectively. A total of 170 Or genes were annotated in the bee, of which seven are pseudogenes. These constitute five bee-specific subfamilies in an insect Or family tree, one of which has expanded to a total of 157 genes encoding proteins with 15%-99% amino acid identity. Most of the Or genes are in tandem arrays, including one with 60 genes. This bee-specific expansion of the Or repertoire presumably underlies their remarkable olfactory abilities, including perception of several pheromone…

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  National Institutes of Health