Prevalent bee venom genes evolved before the aculeate stinger and eusociality

BackgroundVenoms, which have evolved numerous times in animals, are ideal models of convergent trait evolution. However, detailed genomic studies of toxin-encoding genes exist for only a few animal groups. The hyper-diverse hymenopteran insects are the most speciose venomous clade, but investigation of the origin of their venom genes has been largely neglected.ResultsUtilizing a combination of genomic and proteo-transcriptomic data, we investigated the origin of 11 toxin genes in 29 published and 3 new hymenopteran genomes and compiled an up-to-date list of prevalent bee venom proteins. Observed patterns indicate that bee venom genes predominantly originate through single gene co-option with gene duplication contributing to subsequent diversification.ConclusionsMost Hymenoptera venom genes are shared by all members of the clade and only melittin and the new venom protein family anthophilin1 appear unique to the bee lineage. Most venom proteins thus predate the mega-radiation of hymenopterans and the evolution of the aculeate stinger.

Automated summary

Most venom genes in Hymenoptera are shared by all members of the clade, with single gene co-option being the primary source and gene duplication contributing to diversification. Only a few venom proteins, such as melittin and anthophilin1, appear to be unique to the bee lineage, suggesting that most venom proteins predate the evolution of the aculeate stinger and the mega-radiation of hymenopterans.