Insecticidal effects of a recombinant baculovirus expressing scorpion toxin LqhIT2

A system of the baculovirus Bombyx mori nucleopolyhedrovirus (BmNPV) and the silkworm larvae, B. mori, was applied to analyze the potential use of the insect-specific toxin LghIT2 for improving the efficiency of recombinant baculoviruses for pest control. The LghIT2 gene, along with the signal sequence for secretion, was synthesized and transferred into the BmNPV genome to generate the recombinant virus BmLqhIT2. Larvae infected with BmLqhIT2 showed LqhIT2-specific symptoms at 48 h post injection (p. i.), stopped feeding at 60 h p. i., and became motionless by 84 h p. i. Particularly, the larvae infected with BmLghIT2 stopped moving 24 h earlier than those infected with BmAaIT, which expressed another insect-specific scorpion toxin AaIT. An N-terminal sequence and mass spectrometric analyses showed that BmLqhIT2 produced mature LghIT2. The present results suggest that LqhIT2 is more efficient than AaIT for improving the Insecticidal activity of baculoviruses.