Abstract: ATP-binding cassette transporters (ABC transporters) are a recently documented family of detoxification-involved enzymes following cytochrome P450 monooxygenases (P450s), glutathione S-transferases (GSTs) and carboxylesterases (COEs). Over the last few years, these enzymes have been getting broad recognition and receiving extensive attention because of their important functions in the detoxification of insecticides. The ABC transporter is one of the major transmembrane protein families, which comprises four core domains with two highly conserved domains or nucleotide binding domains (NBDs) and two highly hydrophobic transmembrane domains (TMDs). In arthropods, the ABC transporter gene family can be divided into eight subfamilies (ABCA-ABCH), which vary in the number of members and their functions, based on the similarity of amino acid sequences and the conserved domains. These proteins are distributed in all living organisms on earth, and exhibit many vital roles including substrate transporters, signal transduction, cell-surface receptor, and special roles in DNA repair, translation and regulation of gene expression. In addition, recent advances in this area have shown that the mutation and/or overexpression of ABC transporters in arthropods are associated with the resistance of both pesticides and Bt toxins. In fact, they may potentially threaten the sustainability of Bt crops. This article presents an overview on the molecular structure and ATP-driven functions of the ABC transporters, and also the classification, molecular structure and physiological functions of the ABC-transporter subfamilies. We also described the research progress made on insecticide resistance mechanisms mediated by the ABC transporters in hoping to provide some basis for improving monitoring and management strategies of the insecticides used for pest control in agroecosystems.

Key words: Arthropod, ABC transporter, molecular structure, subfamily, physiological function, mediated resistance