전국적으로 매년 말벌 벌집 신고수는 약 20만건이 넘으며 부상자는 1-2만명, 사망자도 10-15명씩 나타나고 있다. 이에 따라 매년 소방청에서는 여름과 가을에 벌 쏘임 사고 ‘주의보’를 발령하고, 벌 쏘임 사고 예방에 대한 주의를 요하고 있다. 이처럼 말벌은 강력한 독침을 가진 사회성 곤충으로 외부 천적으로부터 그들의 군집을 지키 기 위한 방어행동이 매우 잘 발달되어 있다. 말벌은 외부의 인위적인 자극에 대해 천적의 침입으로 인식하고 집단 공격을 하는데 주로 검은색과 같은 짙은색의 긴털을 가진 대상에 대해 강한 공격성을 보였으며, 초록색, 노란색과 같은 자연색에는 크게 반응하지 않았다. 집단 공격시 약 10-15m 정도까지 추적하면서 공격을 하였고 천적이 벌집으로부터 약 3m 이내에 들어오면 경계 비행 후 공격하였다. 따라서 말벌 위험 지역에서는 이러한 특성을 잘 파악하여 행동하는 것이 말벌의 피해를 줄이는 방법이다. 또한 말벌의 독성 강도는 장수말벌의 독이 가장 강했으며 그 뒤로 꿀벌, 좀말벌, 털보말벌, 등검은말벌, 말벌, 왕바다리 순으로 나타났다.

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 31 venom-specific genes were identified in both venom gland transcriptomes but their expression profiles were different between V. crabro and V. analis. Venom allergen 5, premastoparan A and phospholipase A were the top three genes that were most prevalently transcribed in the venom gland of V. crabro, and their transcription rates were 902-, 112- and 4164-fold higher compared with V. analis, respectively, as judged by FPKM values. Their differential transcription profiles were confirmed by quantitative real-time PCR. In the venom gland of V. analis, however, premastoparan A was most abundantly transcribed gene, followed by calponin and tropomysin. In general, most venom-specific genes were more abundantly expressed in V. crabro but some genes exhibited higher transcription rates in V. analis, including muscle LIM protein, troponin, paramyosin, calponin, etc. Our findings suggest that V. crabro produce venom with much more enriched venom components, thereby with higher toxicity compared with V. analis.

To investigate genes differentially expressed in the venom of social and solitary wasps, a comparative transcriptome analysis was conducted. Subtractive expressed sequence tag (EST) libraries specific to the venom gland and sac (gland/sac) of a social wasp species, Vespa tropica and a solitary hunting wasp species, Rhynchium brunneum, was constructed by suppression subtractive hybridization. In BLASTx analysis, 41% and 56% of the total ESTs showed statistically best-matched hits (E ≤ 10-4) in the libraries of V. tropica and R. brunneum, respectively. Although the functional category analysis did not show remarkable differences in the distribution of functional categories between the two venom gland/sac cDNA libraries, perhaps due to the lack of functional information on many of the venom components, there were groups of genes that are specific to either V. tropica or R. brunneum. Venom allergen 5 and serine protease were found to be social wasp-specific venom transcripts. In contrast, venom peptides, metalloendopeptidases, arginine kinase and dendrotoxin were observed in solitary wasp at much higher frequencies.