Bacillus thuringiensis vegetative insecticidal protein family Vip3A and mode of action against pest Lepidoptera.

Vip3A proteins are widely used for controlling pest Lepidoptera. Different binding sites with different receptors in the insect midgut membrane and lack of cross-resistance with crystal (Cry) proteins enhance their applicability, as both single proteins and proteins pyramided with Cry proteins in transgenic Bt crops. Vip3A proteins are effective but there is relatively little information about their structure, function, activation, specificity, and mode of action. In addition, the mechanism of insect resistance to these proteins is unknown. Phylogenetic analysis and multiple sequence alignment showed that Vip3A proteins are genetically distant from Cry proteins. The mode of action and insecticidal activity of Vip3A proteins are discussed in this review. This review also provides detailed information about the Vip3A protein family that may aid in the design of more efficient pest management strategies in response to insect resistance to insecticidal proteins.