Comprehensive and functional venomics of social wasps Vespa crabro flavofasciate Cameron and Vespa analis parallela Andre

Vespa crabro is a cosmopolitan social wasp species whereas Vespa analis is commonly found in Asia. Both species are widely distributed in Korea and known to be aggressive when disturbed, resulting in frequent sting accidents. Although major venom components of well-known Vespa wasps have been reported, no comparative transcriptomic analysis of venom gland between V. crabro and V. analis has been conducted to date. To investigate the differences in venom properties between these two wasps, total RNA was extracted from each venom gland and used for RNA-sequencing. A total of 36 and 37 venom-specific genes were identified in venom gland transcriptomes from V. crabro and V. analis and their expression profiles were different. Prepromastoparan A, Vespid chemotactic precursor and vespakinin-T were the top three genes that were most prevalently transcribed in the venom gland of V. crabro, and their transcription rates were 112-, 16- and 161-fold higher compared with V. analis, respectively, as judged by FPKM values. Their differential transcription profiles were confirmed by quantitative real-time PCR. Our findings suggest that V. crabro produce venom with much more enriched venom components, thereby resulting in higher toxicity compared with V. analis. In an attempt for the functional analysis of venom components, mastoparans of both V. crabro and V. analis were synthesized and their bio-activities were compared. The V. analis mastoparan exhibited similar levels of antimicrobial activities against model bacteria and fungi but significantly higher antitumor activities against human ovarian tumor cell lines compared with the V. crabro mastoparan.