Toxin diversity revealed by the venom gland transcriptome of Pardosa pseudoannulata, a natural enemy of several insect pests

The pond wolf spider, Pardosa pseudoannulata, is one of the most dominant predators of several agriculture insect pests including mainly the rice planthoppers and leafhoppers in paddy fields in Asia. Venom has been an attractive subject as the powerful weapon of spiders due to the complex components secreted from venom gland. The transcriptome of P. pseudoannulata venom gland was sequenced in order to understand the diversity of venom components at the molecular level and provide a new perspective for insect pest management. A total of 48 potential peptide toxins were identified from 75,980 assembled transcripts. Among them, 32 putative neurotoxin precursors were classified into six families systematically. In addition to neurotoxins, peptide toxins with potential antiviral and antifungal activities were annotated as well as the protease inhibitors. The diversity of P. pseudoannulata venom was firmly demonstrated with the presence of astacin-like metalloprotease toxins, Kunitz-type serine protease inhibitors, venom allergen 5, hyaluronidase and other important venom components. In addition, the tissue expression profiles of the toxin-related genes were investigated in venom gland, brain, and fat body. The present study classified the diverse venom components P. pseudoannulata and provided essential information of potential insecticidal toxins for the biological control of insect pests.