Molecular Characterization of Mutations in Anticarsia gemmatalis Cadherin Gene and their Relation to Bacillus thurigiensis Resistance

Anticarsia gemmatalis Hübner, 1818 is the main soybean defoliating pest in Brazil. The biological control of species done with products based on toxins produced by Bacillus thurigiensis (Bt), as bioinsecticides, or transgenic plants. After activation intestinal proteases, these interact receptors, especially cadherin, leading to death due formation cellular pores. In recent years resistant populations have been identified laboratory, which can be a problem if same patterns are found crops, reducing their effect. this paper, we performed comparative structural analysis mutation region for gene receptor A. gemmatalis, among and susceptible strains treated toxin Bt (Cry1Ac). HaCad fragment cadherin was amplified PCR, sequenced, analyzed bioinformatics tools. PCR results were positive specimens but not strains, suggesting presence strain. sequenced fragments insects, six haplotypes found, originated amino acid sequences demonstrated modification four sites, did interfere three-dimensional shape protein. These data showed considerable variation taking into account size fragment, even they do affect final structure allowed better understanding mechanisms resistance Cry1Ac species, mainly involvement process.